666 Park Avenue: NYC’s most palatial, mysterious maisonette
Second Story
SubscribeSign in
Discover more from Second Story
A newsletter for those who love old houses and history.
Over 6,000 subscribers
Subscribe
By subscribing, you agree Substack's Terms of Use, and acknowledge its Information Collection Notice and Privacy Policy.
Already have an account? Sign in
666 Park Avenue: NYC’s most palatial, mysterious maisonette
The 27-room triplex, known as the most remarkable apartment of its kind, is hidden within the base of one of the city's notoriously exclusive co-ops.
Apr 25, 2025
181
18
24
\ \ mistercicerone\ \ 1,273 posts · 25K followers\ \
666 Park Avenue Maisonette!
As the 1920s progressed districts that had formerly been exclusively residential became more and more commercial, a destiny to which many areas of the city had been subject over the previous three centuries of Manhattan’s development. Owners of most one-family row houses whose neighborhoods were no longer suitable for home ownership were content to buy apartments within the broad market of offerings being created by developers. Large apartments, duplexes, even triplexes or penthouses, were sufficient to lure the former house owners.
For those who dwelled in the huge mansions of Fifth Avenue the shift to multifamily living arrang ments was not so readily made. They were used to distinctive residences and would not be satisfied with ordinary apartments, regardless how luxurious. With commercial development edging out existing residences all along Fifth Avenue south of East 59th Street, this market was significant, if not overly large.
One way of making apartment-house living com parable to the experience of living in a free-standing private mansion is to provide the equivalent of an individual house and then surround it with an apartment building. The resultant mini-house or maisonette can have the accommodations and convenience of the most lavish multi-floored apartment along with the privacy inherent to a one-family home.
Comment maisonette below!
BW Photos and text courtesy of Andrew Alpern. Color photos from arch digest. Check out @notenoughangers newsletter for a long article on this maisonette. I sourced some photos from here too. For blue prints check out @davidnettosays
#vanderbilt #maisonette #apartmenthouse #architecture #gildedage #federalstyle #neogeorgianarchitecture #classicalarchitecture #georgianarchitecture #famousapartment #famousinteriordesign #mrsvanderbilt #vanderbiltmansion #parkavenue #newyorkcity #uppereastside #lenoxhill #classicalapartment #mysteryapartment
Welcome to Second Story, a weekly newsletter for those who love old houses and mysterious maisonettes. Subscribe below if you’re not already on the list. This newsletter is entirely reader supported—join in on the prewar floorplan fun!
The most legendary prewar apartments in New York City history have one thing in common: They no longer exist. From Condé Nast’s 30-room penthouse at 1040 Park Ave to Marjorie Merriweather Post’s legendary triplex, these mansions in the sky—along with so many others—were subdivided into smaller suites after the original tenant vacated.
One New York palace, though, has quietly survived: the stupendous 27-room triplex maisonette in the base of 660 Park Avenue, one of the Upper East Side’s searingly exclusive co-ops. The most remarkable apartment of its kind, it’s shrouded in secrecy, thanks to a scarcity of photos and one extraordinarily difficult to locate floorplan. Today, though, I’m shining a light on this mysterious maisonette, with a history almost as intriguing as its custom address: 666 Park Avenue.
What is a maisonette?
In short, a ground-floor apartment with a dedicated street entrance. A maisonette strikes a balance between apartment and townhouse living, offering the privacy of a separate entrance without sacrificing the convenience of building services and staff. Many maisonettes are one floor, but others in especially grand buildings— like 820 Fifth Avenue—are two floors. 666 Park Avenue, not to be outdone, is three, and uniquely has its own address separate from the main building.
The Main Building: 660 Park Avenue
600 Park Avenue. The maisonette, 666 Park Ave, takes up the first three floors.
At the corner of East 67th Street, 660 Park Avenue was completed in 1927 by York & Sawyer, the classical architecture firm behind other buildings like the New York Historical Society and the New York Athletic Club. The distinguished 14-story co-op does not allow financing 1 and has just 12 residences, mostly full-floor 13-room apartments.
A typical apartment at 660 Park Avenue.
The building, with its strong cornice, serene facade, and boldly carved limestone base, draws inspiration from Renaissance palazzos. The maisonette’s grandeur is visually defined on the exterior, where the casement windows on upper floors are exchanged for monumental sashes that hint at the palatial entertaining rooms inside. The maisonette is contained within the limestone base, separated from the rest of the building by a belt course and balustrade.
Second Story is for anyone who loves prewar apartments, fabulous floorplans, curious histories, and insider-y architecture and interiors tips you can’t find anywhere else! Paid subscriptions are just $6/mo or $60/yr.
Subscribe
The Maisonette: 666 Park Avenue
The maisonette entered society not unlike a debutante, with an announcement in The New York Times. “MRS. VANDERBILT’S HOME” the headline proclaimed one Sunday in March 1927, “New three-floor apartment at 660 Park Avenue ready soon.”
Virginia Fair Vanderbilt, freshly divorced from William K. Vanderbilt, Jr., had been living in the family’s Stanford White-designed mansion at 666 Fifth Avenue, when she decided it was time for a change as Fifth Avenue was becoming a commercial thoroughfare.
666 Fifth Avenue, the Vanderbilt House.
She sold 666 Fifth to a developer and planned to join other families of the 400 uptown. The Times reported that she bought the first three floors of 660 Park Avenue for $195,000 ($3.6M today) to build a custom spread, not unlike what Marjorie Merriweather Post did atop 1107 Fifth Avenue just two years prior. Like Marjorie—who demanded her triplex share an address with her mansion—Virginia appears to have orchestrated a similar move: although her apartment was within 660 Park Ave, the maisonette would carry a separate address, 666 Park Ave, to recall her former home on Fifth 2.
“Each floor is 60 by 100 feet, permitting 13 rooms to a floor,” reported The Times as it gave the first hints of the space. “Mrs Vanderbilt, however, is not going for numerical superiority. In her apartment there are 27 rooms, some of them duplex in character.” How grounded of her.
The separate entrance to the maisonette, 666 Park Avenue. It is directly to the left of the main entrance of 660 Park. Via @Machineforliving.
But Virginia would never complete the apartment as planned. The following year, The Times announced that she sold the palatial (yet unfinished) apartment to the president of National Distillers, Seton Porter. “This is generally considered one of the finest apartments ever built in New York,” described The Times 97 years ago today, on April 25, 1928. Virginia would go on to land at a townhouse in the East 90s.
Seton Porter oversaw the installation of the vast rooms, sourcing paneling not from the offices of York & Sawyer but from European manors and castles to bestow generational history and importance to the new home.
There is unfortunately no publicly available floorplan—I tried contacting Columbia University which has the archives of York & Sawyer, the DOB, and the Office of Metropolitan History 3—and the apartment has really only been photographed three times: Once when Seton Porter owned it, once when Leslie Samuels owned it, and once by Architectural Digest in March 2002. However, I did manage to find an adequate formal description of the apartment in New York’s Fabulous Luxury Apartments by Andrew Alpern from 1975.
The drawing room when owned by Seton Porter. Via @MachineforLiving and @johnyunis on Instagram.
“A flight of broad marble steps leads to a foyer whose walls are carved Caen stone. On this level is a double-height living room, a double-height dining room, and a double-height library, as well as a study, the kitchen, service pantries and the servants’ hall. The second level includes separate men’s and ladies’ coat rooms and six servants rooms. The third level contains the master suite (bedroom, sitting room, dressing room and bath) plus two other master bedrooms (each with its own bathroom) as well as a sewing room, extensive closet space, and five additional servants rooms.”
I would expect that the roughly 18,000 square foot apartment has more than just three principal bedrooms, especially if there are (at least) 11 staff rooms. Other descriptions of the apartment have noted that there is a charming card room off the library, “a reminder that this is an apartment laid out for a certain way of life.”
165K followers
\ \ johnyunis\ \ 3,414 posts · 165K followers\ \
666 Park Avenue, Part 2, Drawing Room. East view. According to a June1926 article in the New York Times, Mrs. William Kissam Vanderbilt II was the first owner of this maisonette – she bought it before the building was completed and probably supervised it's layout, as the article states that her drawing room would be 22' x 46', her library would be 18' x 23' and all principal rooms would have a ceiling height of 18 feet. Yes, this contradicts the information in the Architectural Digest. Not sure which is correct, or which parts of each one are correct LOL Anyhow, apparently Mrs. Vanderbilt never moved in. The first occupants of record are the Seton Porters, who hired a group of architects, including F. Burrall Hoffman of Vizcaya fame, to make alterations. It is unclear if Mrs. Vanderbilt installed the 17th and 18th century rooms or if the Seton Porters did. As Hoffman used many period rooms at Vizcaya and the Vanderbilts were not particularly known for period decor, my guess would be that Hoffman installed the paneling... just a guess😊 Here we have another view of the 17th century paneling from Spettisbury Manor. Edouard Manet's Buste de Femme Nue, 1875, is above the mantel. Claude Monet's Mont Kolsaas, Effet Rose, 1895, is at left. This is from the article in #architecturaldigest #666parkavenue #660parkavenue #maisonette #mansion #18thcentury #17thcentury #parquetdeversailles #paneling #boiserie #SpettisburyManor #english #french #furniture #architecture #interiordesign #impressionist #chinese #apartment #furniture
UPDATE [August 6th, 2025]: The designer and writer David Netto has done the impossible and located the floorplan! These plans are from Seton Porter’s time owning the apartment, when he installed the incredible main rooms. Indeed, the maisonette does have just three main bedrooms and is consistent with Alpern’s description. The second floor seems to be more of a mezzanine with the coat rooms and staff quarters. An incredible find! Click though and be prepared to zoom in.
62.1K followers
\ \ davidnettosays Verified\ \ 7,379 posts · 62K followers\ \
You’ll have to squint, but here’s something you don’t see every day—the complete and never before shown plans for the triplex maisonette at 666 Park Avenue (previous post), showing modifications as specified for first occupant Seton Porter (May 1928). This is when the living room paneling from Spettisbury House went in and the rooms took on the baronial English character they retain to this day. Burrall Hoffman as consulting architect makes sense as he would have just finished work on Vizcaya; the field dimension notes may be in his hand
Undoubtedly the crown jewel of the apartment is 50-foot long, 24-foot high living room with elaborately carved early 18th-century pine paneling 4 from Spettisbury House in Dorset. Spettisbury House was built in 1740 and demolished in 1927 after being used as a convent and school. Many of the rooms in the great house were sold off to Americans looking to imbue their homes with a sense of European gravitas. That included the magpie-like William Randolph Hearst, who reportedly first purchased the living room before selling it during bankruptcy.
Spettisbury House, where the living room paneling came from.
The living room leads directly into an equally vast dining room, anchored by a fireplace and thick band of crown molding. Also on the principal floor is the library, finished in paneling sourced from a house in Grosvenor Square in London. Other rooms upstairs were sourced from Chateau de Courcelles in Sarthe, France.
The most grandly scaled rooms are on the second floor and the more intimate “family quarters” on the third floor, as Architectural Digest described in a March 2002 feature.
The hallway of the second floor when Seton Porter owned 666 Park. I believe this hall separates the drawing and dining rooms. Via @ machineforliving.
While we can’t cross reference this description with a floorplan (rude), it is consistent with a description provided by philanthropist Leslie Samuels, who owned the apartment from 1952 to 1981 with his late wife, Fan Fox.
"Every night when my wife [Fan Fox Samuels] was alive, we'd dress for dinner,” Leslie Samuels, the fifth owner of the apartment, described to The Washington Post in 1981 when he listed the maisonette for $9M. “We'd have our drinks in the drawing room, and then, after dinner, we'd come up here [to a smaller sitting room]."
The smaller drawing room as it was and as is is currently (below). This is on the third floor, which you can tell by the windows. Via @machineforliving on Instagram.
165K followers
\ \ johnyunis\ \ 3,414 posts · 165K followers\ \
666 Park Avenue, Part 6, Medallion Room, as it appeared most recently. Elsewhere in the apartment are two rare Louis XIII rooms, both of which came from the Chatêau De Courcelles, in the Sarthe in northwestern France, and were probably installed by F. Burrall Hoffman for the Seton Porters in the late 1920's. The one that we see here is called the medallion room. Obviously, the painting is extraordinary. In the corner, a pre-Columbian vessel rests on an 18th-century English card table. The third century BC figure lies on a Quing Dynasty low table. From the 2002 article in @archdigest . #666parkavenue #660parkavenue #maisonette #mansion #18thcentury #17thcentury #parquetdeversailles #paneling #boiserie #chateaudecourcelles #louisxiii #french #furniture #architecture #interiordesign #impressionist #chinese #apartment #furniture
Samuels was referring to a room clad in Louis XIII paneling from the Chateau de Courcelles, which The Washington Post reported was complete with oak-beamed ceilings and a fireplace with original briques from Feucherolles and a parquet floor from the Chateau de la Muette. Another reclaimed room from France, used as a bedroom, featured painted chinoiserie paneling and a stone fireplace.
As Seton Porter had it (left), and as the Sackler family had it (below). Via @machineforliving on Instagram.
165K followers
\ \ johnyunis\ \ 3,414 posts · 165K followers\ \
666 Park Avenue, Part 8, Louis XIII Chinoiserie Room, as it appeared more recently. This is the other Louis XIII room from Château de Courcelles, which was probably installed by architect F. Burrall Hoffman for the Seton Porters- a very early example of French chinoiserie boiserie. The canopy bed is Ming Dynasty. Again, extraordinary painting – even the stone fireplace is painted. From the 2002 article in @archdigest #666parkavenue #660parkavenue #maisonette #mansion #18thcentury #17thcentury #parquetdeversailles #paneling #boiserie #chateaudecourcelles #louisxiii #french #furniture #architecture #interiordesign #chinoiserie #chinese #apartment #furniture
The maisonette has had six owners since it was completed nearly a century ago, and they have all shared a respect for the architecture and history of the fabulous apartment. Keep in mind: These interiors are by no means protected. They could easily have been ripped out sometime over the years, just as the interiors of Jackie Kennedy’s apartment were gutted upon its sale to David Koch in 1996. Not so at 666 Park, which did undergo some renovations in 1952 when Leslie Samuels purchased the maisonette, but the principal rooms with their period boiserie have survived untouched.
The library, clad in paneling from a townhouse in Grosvenor Square in London. On the left is the library as Leslie Samuels had it. Below is as it was in 2002. Via @Johnyunis / the book "Living with Antiques"
165K followers
\ \ johnyunis\ \ 3,414 posts · 165K followers\ \
666 Park Avenue, Part 11, Library, south view, as it appeared more recently. Sorry, but this is the only color photo that I have of the library. According to Christopher Gray, the Porters "...installed at least four antique rooms: A dining room from a house in London, a pine room from Spettisbury Manor in England for the main salon, and two rooms from the Château de Courcelles in France." We will see the dining room next, which does not have paneling, and we have already seen three antique rooms, so the "dining room from a house in London" is likely this room. There is also a slightly inaccurate article from the Times in 1981, which refers to "sections of Georgian paneling from a house on Grosvenor Street in London.", which could refer to this room... Perhaps this room was a dining room and the paneling was altered at one end to accommodate books? Also, not sure that this room was always painted, as the door surrounds and corner niches are unpainted pine. The next two black and white photos will show the room better. The caption reads: "16th century Italian majolica plates and pharmacy jars are displayed in a corner niche of the library. A second century A.D. funerary bust is in the foreground." From the 2002 article in @archdigest #666parkavenue #660parkavenue #maisonette #mansion #18thcentury #17thcentury #parquetdeversailles #antique #paneling #boiserie #grosvenorstreet #georgian #french #furniture #architecture #interiordesign #interiors #apartment #furniture
The maisonette represents a truly rarified way of life, one of bygone grandeur and formality. Whenever I bike by those oversized windows facing Park Avenue, that’s what I think about most: How does life unfold inside the maisonette? What does a 666 Park Avenue dinner party look like?
“The Samuels family often had 20 for dinner,” Maria Carle, one of their 12 members of staff to Leslie and Fan Fox Samuels recalled to The Washington Post. "For 20 people, [Mrs. Samuels would] have five waiters for the table. She liked to do everything right. She was very precise.”
165K followers
\ \ johnyunis\ \ 3,414 posts · 165K followers\ \
666 Park Avenue, Part 14, Dining Room, north view, as it appeared most recently. Through the double doors visible in the center of part 1 is the dining room. In that photo, it appears as if the drawing room opens directly into the dining room, however, although the doorways line up, there is a hallway in-between that is lit by one window identical in size to the ones in the drawing room and dining room. While the dining room and drawing room seem to share a similar, if not identical, ceiling height, the dining room is much shorter, having only two large windows along Park Avenue, compared to the four of the drawing room. My best guess is that the dining room shares the width of the drawing room and is less than 30 feet in length. Not sure that this room ever had paneling- doubt that it did. The walls may have been covered in a damask or Fortuny-like fabric while the Samuels' lived there, however not certain of that either! The caption says "A pair of bishop saint panels, circa 1380, flank Filippo Parodi's mirror frame, Jupiter and the Fall of the Giants, which hangs above a Venetian glass mantelpiece. The 14th-15th century Infant St. John, Virgin Mary and Angel is by the window". From the 2002 article in @archdigest #666parkavenue #660parkavenue #maisonette #mansion #18thcentury #17thcentury #parquetdeversailles #antique #paneling #boiserie #grosvenorstreet #georgian #french #furniture #architecture #interiordesign #diningroom #chinese #apartment #furniture #interiors
Carle continued: “Every morning they'd have breakfast at 11:30. He'd eat down here, but Mrs. Samuels would have her upstairs…Then they'd read their mail and then go out window shopping in their car with the chauffeur, or perhaps to some exhibit. They liked to come back with some little pretty things for the house."
Leslie and Fan Fox were married for 41 years before she passed away in 1981. Leslie wasted little time before moving into a smaller apartment at the Waldorf. "I couldn’t stay here any longer after she died," Leslie Samuels said. "Everything here we bought together. We were always together.”
165K followers
\ \ johnyunis\ \ 3,414 posts · 165K followers\ \
666 Park Avenue, Part 17, Master Bedroom, as it appeared most recently. According to the caption: "18th-century painted and gilded French boiserie defines the master bedroom. Hanging above the bed is Ballerina by Edgar Dégas. Over the two French marquetry commodes are a still life by Pierre Auguste Renoir, left, and a landscape by Henri Rousseau." Just a guess, but the commodes look 18th-century to me. Not sure that it will be visible on Instagram, but the ceiling forms a cove above the paneling, so I would guess the ceiling height to be certainly above 10 feet and perhaps even close to 12 feet. #666parkavenue #660parkavenue #maisonette #mansion #18thcentury #17thcentury #parquetdeversailles #antique #paneling #boiserie #grosvenorstreet #georgian #french #furniture #architecture #interiordesign #masterbedroom #bedroom #apartment #furniture #interiors
The maisonette last traded back then, when it was sold by New York real estate icon Edward Lee Cave for $9M ($31.6M today). It was bought by Arthur Sackler, who lived there until his death in 1987 with his wife, Dame Jillian Sackler, who reportedly still calls the maisonette home today.
She welcomed Architectural Digest into the maisonette 23 years ago, in March 2002. Writer Michael Frank centered the profile around how the Sackler art collection complemented the impressive architecture of the home.
“It’s been a great privilege to live here,” Dame Jillian said in the feature. “My relationship to the apartment… is only temporary.”
The bath and dressing room of Mrs. Porter. In the Architectural Digest feature, they mention that Dame Jillian Sackler's bathroom is art deco. I hope that means this bath has survived! Via @Machineforliving on Instagram.
Over lunch recently, a friend described homeownership as a kind of stewardship—that we don’t own homes so much as we preserve them for the next generation. Dame Jillian’s words echo that philosophy, knowing she’s just one in a line of those entrusted with preserving this remarkable place. Whoever comes along next won’t just acquire a trophy apartment. They’ll assume the task of protecting one of the last prewar icons: the Maisonette at 666 Park Avenue.
Second Story is a reader-supported newsletter. If you like what you read, please consider becoming a paid subscriber so you don’t miss out on what’s next!
Subscribe
That means any purchase must be all cash, and the board will expect applicants to have multiples of the apartment’s value in post-closing funds.
This is kinda unconfirmed, but I would be shocked if this was untrue.
If anyone has leads on a floorplan, please! I am all ears.
Both The New York Times and Architectural Digest say that it’s 17th-century paneling, but everything I found dated Spettisbury House to the early 18th century.
181 Likes∙
181
18
24
PreviousNext
Discussion about this post
CommentsRestacks
Liked by Robert Khederian
Thank you for your work and detail on this.
Like (7)
Reply
Heather Cocks & Jessica Morgan
Liked by Robert Khederian
These interiors are LUXE, wow!
Like (3)
Reply
TopLatestDiscussions
What intact prewar staff quarters look like
Photos from apartments (and mansions!) past.
Nov 25, 2025•Robert Khederian
52
2
5
Some of my favorite prewar floorplans—and how to read them!
Feb 21, 2025•Robert Khederian
154
17
18
Spelunking in an Ansonia apartment
Some of the most interesting spaces on the Upper West Side.
Jan 9•Robert Khederian
42
6
3
See all
Ready for more?
Subscribe