When Roger Zeender is at home in the old Blair Mansion Inn on Eastern Avenue, he lives in Takoma Park, Md. But as soon as he steps off his front porch to water the flowers, he's standing in the District of Columbia.

A woman who bought a house within walking distance of the Takoma Metro says she still has to look at the street signs to know whether she's in Maryland or the District. Even the name of the neighborhood is in dispute because of an old notion that Takoma, D.C., doesn't use the "Park" suffix applied in Maryland.

It's no wonder Takoma has an identity crisis. With a main drag named after one of Maryland's most prominent political clans (the Blairs), addresses in three jurisdictions and a street system that turns 45 degrees off the D.C. grid to match the Maryland layout, it's enough to send anyone to a road map.

"Well, I guess it is rather confusing," admitted Loretta Neumann, one of the founders of Plan Takoma, a preservation-minded group formed in the mid-1970s when it seemed that Metro subway development might "renew" the neighborhood. "But in terms of our friendships and a lot of our activities, we think of it as one community," she said.

Takoma may be a little short on geographic identity, but it makes up for it in style. A century-old, fully integrated, middle-class enclave that began as Washington's first commuter suburb, Takoma was certified as historically significant by the D.C. preservation board in 1980 and entered in the federal listings three years later.

"One of the things we like to say about the community, one of the points we brought up before the preservation board, is that the architecture reflects the community," Neumann said.

"It's friendly and cohesive, and I think a lot of it is that we do have these porches and sidewalks. You walk down the sidewalk, the kids are playing, people are sitting on the porch, you stop for a chat and pretty soon everybody's up on the porch together."

In Takoma, however, the architecture is like art: You may not know what it is, but you know whether you like it. The historic district is a virtual fantasyland of styles: great ramshackle frames with sweeping verandas, two-story Hollywood bungalows with arched stucco porches, neatly restored Victorians with their prim angularity and frivolous eaves, British colonial bungalows, half-shingle saltboxes, Queen Anne, cottage, Shepherd Park brick and colonial revival. It makes most of the metro area seem positively predictable.

Tucked into the northeast corner of the District, Takoma is like a geometry puzzle, one large triangle made up of several smaller ones. Generally defined by Georgia Avenue on the west and Tuckerman Street to the south, Takoma runs over to the District line at Eastern Avenue.

From the lower right-hand corner, Piney Branch runs northeast up into the heart of the historic district, while the old Baltimore & Ohio railroad -- the original inspiration for Takoma's development -- cuts northwest across the grain.

From Georgia Avenue to Blair Road, which curves down along the railroad tracks as a reminder of the days when the politically invincible Blairs owned most of southern Montgomery County, Takoma adheres to L'Enfant's perpendicular design. The alphabet of roads above Whittier has a deliberately bucolic theme: Aspen, Butternut, Cedar, Dahlia, Elder, Fern, Geranium.

East of Blair Road, however, Takoma meanders into a maze of streets that turn catty-corner toward Maryland. And with the spillover of old and restored homes on both sides of the border, the demarcation is even more blurred.

This defiance of geography goes back to Takoma's founding more than a century ago by developer B.F. (for Benjamin Franklin) Gilbert, a sometime partner and political crony of Boss Shepherd.

A teetotaler and visionary who ran the Temperance Dining Room in downtown D.C., Gilbert saw the construction of the B&O Railroad as an invitation to clean country living.

In 1883, he bought and began building homes on about 100 acres of land straddling the tracks on both sides of the D.C.-Maryland boundary.

He named it Takoma after an Indian word meaning "high up, near heaven" -- it's about 350 feet higher than Washington -- but spelled it with a "k" to avoid confusion with Tacoma, Wash.

After the Takoma Park railroad station was finished in 1886, Gilbert bought a second tract of 1,000 acres. The word "Park" was added to emphasize Takoma's healthy distance from the miasmic Foggy Bottom, and the town of Takoma Park was incorporated in Maryland in 1890 with Gilbert as mayor.

(The entire neighborhood was at least philosophically included in the Maryland incorporation: In those days, Washington ended at Boundary Avenue -- what is now Florida Avenue -- several miles away.)

Ever since then, Takoma, D.C., has been a mystery unto itself. According to the Zeenders, the Blair Mansion has had four addresses: the first in the District, the second in Silver Spring, the third in Takoma Park and most recently an address in Silver Spring but with a Takoma Park zip code.

Like many once prosperous but "old-fashioned" areas, Takoma went through a period of decline after World War II, and even now is struggling to establish a firm community base.

In contrast to the upscale Carroll Avenue business district just across the Maryland boundary, Takoma has only a small, semivacant commercial strip that runs between a liquor store and the old Takoma Theatre near Fourth Street and Eastern Avenue.

"Historic Takoma covers both" jurisdictions, Neumann said, "but I would say what tends to happen is that when we go into things together, the Maryland side seems to wind up in control of things on both sides."

Bill Boyd, who owns the Takoma Station jazz club on Fourth Street and is developing a larger club across the street, said, "Yeah, the {District} has missed the boat on this one. This is a beautiful community, a neighborhood of professionals. It ought to be doing better" by small businesses.

Residential property values are picking up more rapidly on the Maryland side, too.

According to figures compiled by the Rufus S. Lusk & Son real estate information service, the single-family homes sold in the Montgomery County portion of Takoma Park in 1986 had an average price of nearly $115,000, while homes in the Prince George's County section averaged nearly $91,000. Single-family homes in Takoma, D.C., went for an average of just under $81,000.

On the other hand, the apparent price gap must be considered in light of the difference in the amount of turnover.

There were 222 single-family homes sold in Takoma Park-Montgomery last year, and 156 in Prince George's, compared to only 22 in the D.C. portion.

Stability is at the heart of Takoma's revival, according to Neumann. Takoma is one of seven communities in Neighbors Inc., an organization formed in the late 1950s to fight white flight and, at the same time, prevent block-busting.

"We're very proud that we're an integrated community," Neumann said.

"We want people to move in, we want people to stay. We have a lot more to do here."