In Park Slope, Queen Anne-style mansions are nestled between brownstones, neoclassical townhouses, and steeple-topped churches. The quiet, tree-lined neighborhood is famous for its eclectic mix of well-preserved 19th century architecture, yet a city historic district created for Park Slope in 1973 only covers roughly one-fifth of its area.

A rise in development outside of the protected zone in recent years has prompted the Park Slope Civic Council (PSCC) to push for an expanded historic district that would cover the entire neighborhood. At a March 5th meeting, PSCC presented its ambitious plans for the first time in public to residents and representatives from the Landmarks Preservation Commission (LPC).

"Park Slope is just loaded with historic buildings and a sense of place," said David Alquist, a PSCC trustee. "We think the historic definition covers all of Park Slope."

The current historic district encompasses a narrow swath of Park Slope blocks bounded roughly by Prospect Park to the east, Flatbush Avenue to the north, and Fourteenth Street to the south. Most of the historic district lies between the park and 7th Avenue, leaving nearly all of the neighborhood west of 6th Avenue unprotected.

In 2007, Alquist said, PSCC launched a comprehensive study of the neighborhood, consulting city preservationists and historians and conducting extensive field surveys to identify areas of Park Slope that deserve historic district designation. The result is a proposed study area of 4,500 buildings - or the rest of Park Slope - the civic group believes should be landmarked.

"What we think we've found is a largely intact, largely unprotected late-19th century residential and commercial neighborhood," said Alquist. "We feel we have to do whatever we can to preserve all this and bequeath it to the next generation."

Kate Daly, LPC's executive director, expressed support for the project but said the 4,500 building proposal was far too large.

"Park Slope is an obvious candidate for an expansion of the existing [historic] district," said Daly. “However, the Commission is not going to be able to pass a nearly 5,000 building extension to the district this year."

Daly suggested the civic group work with LPC to create several smaller historic district expansion proposals of perhaps 1,000 homes or less that could be approved and phased-in over time.

LPC, said Daly, only landmarks between two and five neighborhoods a year, but already has a waiting list of roughly 50 neighborhoods that have asked for landmark status. The commission is currently reviewing two dozen of them, including Park Slope, said Daly. According to Daly, LPC typically approves historic districts closer in size to the 450-home Crown Heights North district designated in 2007.

Alquist said PSCC was willing to breakup its massive proposed study area into phases.

"We understand [the LPC's] position and we will take the lead from them," said Alquist. "We'll do whatever we have to, either in big pieces or small pieces to get this done."

Still, Alquist acknowledged, figuring out exactly which areas, blocks, and houses of Park Slope to preserve now, and which to leave for a later date, could prove difficult, causing some residents to worry that any phased-in expansion would pit block against block - even owners of one house versus owners of another - as everyone vies for landmark protection in a neighborhood full of worthy choices.

Park Slope was originally developed in the last three decades of the 19th century as a suburban community for wealthy business elite looking to escape the already crowded streets of Lower Manhattan, according to Francis Morrone, a noted New York City architecture critic and Park Slope expert.

The neighborhood's unique character stems from its broad variety of architectural styles, Morrone said in a presentation at the meeting, designed by some of the period's leading city-based architects, which represent the entire American architectural oeuvre of the late 19th century.

A walk through the neighborhood reveals gabled Queen Anne homes built in the 1870's beside stately, brick-faced Romanesque houses that had become the style of choice by the mid-1880's, explained Morrone, when the neighborhood began a decade-long development boom. By the end of the century, the Romanesque style was eschewed in favor of neo-classical buildings with imposing columns and elaborately carved white limestone and terracotta facades.

"Ultimately when you're talking about a great neighborhood, you're talking about a neighborhood that hangs together as a whole," Morrone said. "Nowhere in New York City is that truer than in Park Slope."

It was the more-than-century-old PSCC, one of Brooklyn's oldest civic organizations, which called for the original, 1973 historic district designation. Many of the residents who attended last week's meeting were longtime Park Slopers who remembered the first fight for landmark status. They were supportive of a historic district expansion as a means to protect the area from future development.

LPC regulates building development and exterior restoration in historically designated neighborhoods. Daly said the commission, exercises its authority, in partnership with the City Planning Commission and existing zoning laws, to block construction of any buildings the commission thinks would be out-of-place in a given area.

Bob Levine, a PSCC member and chairman of Community Board 6's Land Use Committee, lives outside of the current district and said he would welcome a historic district expansion.

"I strongly support the historic district expansion," said Laila Bibelnieks, who lives inside the current district boundary. "There are so many things in this city that are destroyed that can't be replaced. I think it's a privilege to live in a historic area."

Daly said LPC would schedule a public hearing on the historic district expansion, the first formal step towards City Council approval of the project, once PSCC submits an official proposal.

Because LPC has not yet received a proposal, Daly said she could not say when the commission can expect to approve the expansion. Alquist said PSCC plans to finalize a proposal in the next three months. "

This is a great first step,” Daly said of the meeting. "We're off to a good start."