Manhattan’s closest suburb isn’t in upstate New York, Queens, or New Jersey. In fact, it isn’t even outside Manhattan.

Hidden behind a perimeter of prewar apartment buildings is a sleepy enclave of quaint homes with garages and flowering yards on top of a hill. The Marble Hill neighborhood, geographically part of the Bronx but politically part of Manhattan, is seeing its real estate prices drift toward those of the more affluent borough.

As a logical home base for Manhattan commuters, Marble Hill has seen in the past couple of years construction of a shopping mall with a Target, Applebee’s, and Starbucks; an expanded MetroNorth train station, and a 34-unit luxury rental building, which opened to tenants in July.

Still, the fabric of the neighborhood – a cluster of about 100 quirky homes in various architectural styles typically housing two or more families – has remained intact.

“Marble Hill looks as though an architectural school bought the eight blocks that make up the neighborhood, and gave each classroom a street and each student a block and lot, and said, ‘Build whatever kind of home you want here,'” an associate broker with New Heights Realty who lives in Marble Hill, Lisa Castro, said.

The 42-acre village, named after deposits of dolomite marble once quarried to build government buildings, was originally part of Manhattan and separated from the Bronx by the Spuyten Duyvil Creek. In 1895, a shipping canal was dug separating Marble Hill from Manhattan, turning it into an island. A couple of decades later, the Spuyten Duyvil was filled in, connecting Marble Hill to the Bronx.

The neighborhood has never quite gotten over its identity crisis. It has a telephone area code and ZIP code from the Bronx, but emergency vehicles speed north across the Broadway Bridge from Manhattan. A Bronx community board oversees day-to-day operations in Marble Hill, yet residents receive political representation by Manhattan politicians and must travel to Lower Manhattan for jury duty. Time Warner is the cable provider for Manhattan. Cablevision serves the Bronx. Both service parts of Marble Hill.

Real estate prices hang on such trivial distinctions. Naum Colimitra, whose family has lived in Marble Hill for decades, is asking $2,000 a month for a beautifully renovated 2,000-square-foot apartment on the second floor of the family home on Van Corlear Place. He said his longtime neighbors have scoffed at the price, but apartment seekers from Manhattan appear more inclined to bite. Still, the apartment has been on the market for six months.

“It’s not really the city, and maybe people think it’s not a prime spot,” Mr. Colimitra said.

A brand new 34-unit apartment building on Marble Hill Avenue, called the Emerald Tower for its green glass, has been testing the waters for upscale rental accommodations. It has been on the market since July, and has seen some success. About one third of the building, which has an elevator, laundry room, and roof deck, had been rented by late August, the manager of the building, Pam Sendowski, said.

At the building, developed by Marble Hill Partners, prices range from $900 a month for a ground-floor studio apartment to $3,100 a month for one of two three-bedroom penthouses.

Most of the studios and one-bedroom apartments have been rented, the latest to Columbia University students. Claudia Kidder, who was living in Stamford, Conn., discovered her “two-room studio” apartment on Craigslist.

“I wanted to move back to the city, but looking at rentals in Manhattan, the prices were ridiculous,” Ms. Kidder, who works at 55 Water St., said. “This fits my needs very well.”

Ms. Kidder has been pleasantly surprised at the convenience of the neighborhood, which has an elevated subway stop for the no. 1 train and an expanded MetroNorth station to support ridership that has increased 31% over the past five years. Today, about 700 people ride it daily.

FreshDirect may not yet serve the neighborhood, but Ms. Kidder said she has no problem shopping at Whole Foods at Columbus Circle and carrying her groceries back with her. Such inconveniences may be one reason singles seem to be finding their way to the neighborhood’s rentals as opposed to families. Mr. Colimitra said that perhaps families moving to Marble Hill would rather spend thousands of dollars a month on a mortgage rather than a rental, especially in an area where children can attend public schools like Bronx Science or private schools in Riverdale or Fieldston.

There are opportunities for aspiring homeowners, but they are limited. Marble Hill is a small neighborhood where property owners have typically held onto their homes for decades.

“I find that once houses come on the market, they go immediately,” an associate broker with John Edwards Real Estate, Maria Moragianis, said. “The houses are beautiful and still have their original charm.”

A two-family Victorian home at 17 Van Corlear Place was on the market three weeks when an offer in late August came close to its $699,000 asking price, she said.

Homes lining Marble Hill Avenue, Fort Charles Place, Van Corlear Place, Adrian Avenue, Terrace View, and 227th and 228th streets display a range of architectural features, from peaked turrets and mansard roofs to finials and dormer windows. Perhaps their style could be best summed up as the eccentric Queen Anne architecture of the Industrial Age. But the odd house with the decorative trusses and half-timbering of a Tudor, the stucco walls of a Mission, or the low, linear Prarie School style defy all easy classification.

As prices for these homes push upward, a few houses are now under construction on 228th Street, Ms. Castro said. She first moved into the neighborhood in the mid-1990s and has since purchased and refurbished several homes.

“I wouldn’t be surprised if in the past two years almost every homeowner, regardless of the year built, the size, the architectural details, had a real estate gain of somewhere between $100,000 and $175,000,” she said.

Interest in Marble Hill properties has grown even though the neighborhood has no movie theater, bookstore, upscale grocery store, or other amenities. Lots that have languished for decades are finally being developed, including the one where the Emerald Tower now sits. That lot once housed a property formerly owned by the Roosevelts.

“It was empty and had gotten vandalized,” Ms. Sendowski said. “Everything from stained-glass windows to marble mantelpieces were taken out. After 20 years vacant, the current owners just felt this was the time to develop the property.”