Fifty years ago, George and Sherry Arnstein purchased a two-bedroom unit in a new cooperative apartment building in Foggy Bottom overlooking the Potomac River. The curvy, modern development, called the Watergate, was billed as “the town within the city” and soon offered a wide variety of amenities.

Inside the apartments, living rooms offered river views through floor-to-ceiling windows and featured outlets wired for television. Kitchens included a telephone with a red light signaling messages or deliveries. Bathrooms were fitted with bidets and marble vanities.

Shops, restaurants and tiered fountains eventually encircled the base of the buildings, and a swimming pool was set within a garden landscape.

“This building had everything and the location has only gotten better. I can walk to Whole Foods in Foggy Bottom, Georgetown, Metro and the Kennedy Center,” says George Arnstein, who at 91 still calls the Watergate home (his wife, Sherry, died in 1997).

Now living in his second apartment inside what he calls the “lower denture,” referring to the signature concrete “teeth” wrapping the terraces, Arnstein has seen the fledgling Watergate become an iconic landmark.

The last of its six buildings was completed in 1971, only to become synonymous with political scandal. The following year, burglars broke into the Democratic National Committee headquarters in the Watergate office building, leading to President Richard Nixon’s resignation in 1974.

Like many dwellings in the Watergate, Nancy Conrad’s apartment is linear in layout, with the living and dining spaces and master bedroom extending along the windows and terrace. (Sarah L. Voisin/The Washington Post)

Structural problems, including leaky roofs, plagued the buildings soon after their completion. In May, the three-story parking garage next to the hotel partially collapsed because of excessive weight on its roof.

Those events, however, haven’t stopped the Watergate from being a prestigious, sought-after address.

Residents include members of Washington’s elite, such as former senators Robert J. and Elizabeth Dole, Justice Ruth Bader Ginsburg and former Reagan national security adviser Robert “Bud” McFarlane.

Now listed in the National Register of Historic Places, the 50-year-old Watergate East residential building and its neighboring structures are back in style as emblems of midcentury modern design, which is enjoying a revival thanks in part to the recent “Mad Men” TV series.

Increasingly, renovating Watergate homeowners are paying homage to that era through decor, while enlarging room layouts and upgrading original finishes, including parquet floors and metal kitchen cabinets. They often cite the location, on-site amenities and river vistas as reasons for purchasing outdated units in the buildings.

“Buyers come for the view and stay for the convenience,” says real estate agent Gigi Winston, who specializes in Watergate properties. “No two apartments are alike.”

Prices, she says, range from about $300,000 for a studio to $500,000 and upward for a two-bedroom unit. Larger apartments are listed in the millions. Winston is selling a three-bedroom apartment with a den, remodeled by award-winning D.C. architect Robert Gurney, for $3.3 million.

That residence and many others — about 30 to 40 percent of the units, says Winston — have been enlarged by merging two or more apartments into a single home.

Watergate homeowner Nancy Conrad combined two smaller apartments into a three-bedroom residence. (Sarah L. Voisin/The Washington Post)

Watergate homeowner Nancy Conrad lives in a three-bedroom residence created from combining two smaller apartments. The initial renovation was completed by the previous owner, Paul O’Neill, who was treasury secretary under President George W. Bush.

Conrad, who bought the unit in 2009, was married to the late astronaut Pete Conrad, who became the third man to walk on the moon. She oversees the Conrad Foundation, a nonprofit organization whose mission is to engage students in science and technology through entrepreneurship.

Like many dwellings in the Watergate, Conrad’s apartment is linear in layout, with the living and dining spaces and master bedroom extending along the windows and terrace. More utilitarian spaces, including the kitchen, laundry room and bathrooms, occupy the windowless side of the apartment bordering the public corridor outside the unit. A central hallway connects the rooms on both sides.

“This is my sanctuary,” says Conrad, standing near an Indonesian Buddha statue in the dining area. “I was drawn to the hardscape, the architectural features like frosted glass doors and built-in cabinets throughout the spaces.”

She personalized the interior with eclectic furnishings and modern artwork. Custom touches include an abstract painting in the raised living area that slides open to reveal the TV.

Nancy Conrad personalized the interior with eclectic furnishings and modern artwork. (Sarah L. Voisin/The Washington Post)

For other Watergate homeowners, the buildings’ distinctive modern architecture of concrete and glass is both a source of inspiration and a challenge for remodeling. The complex was designed by Italian architect Luigi Moretti, who worked for Benito Mussolini and was briefly imprisoned at the end of World War II.

“The beauty of the Watergate is the structure,” says D.C. interior designer Jose Solis Betancourt. “The use of curves is very dramatic and the interior walls are not parallel. I love that because it opens up the space to the views.”

Betancourt is putting the finishing touches on the expansion of his Watergate apartment, after buying two-thirds of the adjacent two-bedroom unit (the remaining third was purchased by his neighbor) in 2012. The acquisition allowed him to expand the living area and create a larger kitchen and a guest room suite.

The designer celebrated the original architecture by incorporating large columns into window-framing archways and repeating the effect on the opposite side of the living-dining room. The carpeting in the space seems to run up the walls and onto the ceiling, but those surfaces are covered in moiré wallpaper matching the flooring to create the enlarging effect.

Risë Birnbaum embraced the Watergate’s modern design. (John McDonnell/The Washington Post)

Another homeowner who has embraced the Watergate’s modern design is Risë Birnbaum, who runs a D.C. public relations firm. With the help of District-based Shinberg Levinas Architects, Birnbaum spent about $350,000 on the 13-month remodeling of her $1.3 million co-op during 2006 and 2007. She eliminated the linear layout of rooms by demolishing existing partitions to create an expansive, open loft defined by rounded walls and surfaces. Furnishings are a mix of vintage midcentury and contemporary Italian designs to complement the Watergate’s original 1960s architecture.

“All our windows face the river, a wonderful asset, and I wanted the interior to match our magical view,” says Birnbaum, pointing to a panorama of the Potomac winding past Roosevelt Island. “I’ve always loved midcentury art and architecture. My father was an architect and that was his favorite period, and it obviously rubbed off.”

Spaces for living, dining, cooking and watching TV are combined in the center of the apartment. Only a fabric scrim separates the dining area from the TV lounge. “When I have dinner parties, I just pull the curtain to separate the spaces,” says Birnbaum.

Her bedroom and bathroom flank the living space, and a guest suite is tucked behind the TV lounge. A windowless room next to the kitchen was turned into an office.

Risë Birnbaum eliminated the linear layout of rooms by demolishing existing partitions to create an expansive, open loft defined by rounded walls and surfaces. (John McDonnell/The Washington Post)

“The challenge of renovating in the Watergate is to work with the electrical, plumbing [and] gas lines, which are very old and very difficult to move,” says architect Salo Levinas, who designed Birnbaum’s home. The architect disguised an unsightly utility pipe near the kitchen that couldn’t be relocated within a stainless-steel column fitted with translucent plastic panels and fluorescent lights to illuminate the space.

Lighting is another challenge of renovating in the Watergate, given the concrete ceilings that make it nearly impossible to insert new wiring and fixtures. In Birnbaum’s apartment, soffits were extended from ceilings in the foyer and kitchen to hold small halogen lights. An inverted plaster dome was added to the dining area ceiling to accommodate more lights over the table.

“The ceiling heights are only eight feet,” says architect Chris Landis, who has remodeled four Watergate apartments. “So if you have to put in a dropped ceiling or a soffit for new wiring or ductwork, that lowers the height even more.”

In the living space of Gary Parker’s co-op at the Watergate, modern furniture and vintage movie posters capture a midcentury vibe. (John McDonnell/The Washington Post)

The architect’s District-based design-build firm, Landis Construction, helped Gary Parker, a screenwriter and documentary filmmaker, remodel his Watergate apartment in 2011. Parker bought the one-bedroom unit for $278,500 and spent about $90,000 over six months to modernize the interior. “I wanted to use every square inch wisely.”

He turned a walk-in closet into a sleeping nook and now uses the original bedroom as his office and TV lounge. In the living space, modern furniture and vintage movie posters capture a midcentury vibe. “This is what the interior could have looked like when Watergate East was completed in 1965,” Parker says.

To save money, Parker bought 1950s kitchen cupboards from Craigslist and Community Forklift, a salvage warehouse in Hyattsville. He had the metal cabinets refinished at Bethesda Chevy Chase Auto Body, where they were painted a glossy, fire-engine red.

His outdoor terrace, overlooking Virginia Avenue, serves as another living and dining space furnished with more vintage finds. Pool hall benches from Community Forklift are paired with a vinyl-topped plywood table made by Parker and a glider from Craigslist.

Landis says remodeling in the Watergate can pose logistical challenges for construction trades, from the lengthy process of getting plans approved by the co-op board to finding parking spaces for trucks near the building.

“There are a lot of extra steps that can slow the process down,” Landis says, “and that adds to the price of renovating.”

Deborah K. Dietsch is a freelance writer.