"You want to keep going?" asked Pat Morosetti, uneasily, as he steered a city-owned TrailBlazer along a narrow path across a hill deep in Frick Park.

		Graphic: Pittsburgh's trails

"Yeah. You OK?" said his passenger on that August day, Mayor Tom Murphy.

"This is pretty tight," said Morosetti, Murphy's security detail.

Murphy checked the clearance with the encroaching trees and peered down another winding trail branch. "Let's see if we can figure out a way out of here."

Minus the driver and the internal combustion engine, this is roughly how Pittsburgh's burgeoning network of trails began. "For 20 years, I would run, or occasionally ride bikes, and I would always look for the blank places on the map," Murphy said recently. He kept mental notes, and after becoming mayor in 1994, he started building trails.

Nearly 12 years and $7 million later, the city has 18 miles of biking and hiking trails, up from 2.5 miles in 1993. As his term winds down, Murphy is scrambling to finish a few key links on the North Shore, and in Highland Park, South Oakland and the South Side.

Even with those connections, he won't come close to achieving his dream of a hiking and biking loop through the entire city, with spokes into every neighborhood.

If that's ever to become a reality, it'll take organizational muscle, popular pressure and money the perpetually strapped city may lack.

Murphy said his trail push is more than a function of his personal wanderlust. "The cities that are hot cities to live and work in are cities with amenities like that," he said.

His strategy has been to insist that any new development along the rivers includes a trail. He's been willing to butt heads with banks, nonprofit institutions, and even the Steelers to make sure that happens.

His insistence on leaving room for a trail forced the Steelers to limit their South Side practice fields to 80 yards. "Every time the Steelers get into the red zone and can't score, I feel guilty," he joked.

The cost, of course, goes beyond lost touchdowns. The $7 million the city Planning Department said has been spent on trails during Murphy's tenure includes city, state and federal money, much of which theoretically could have gone to more pressing uses.

Bob O'Connor, the Democratic mayoral nominee, isn't committing to major trail expansions. "Resources should be looked at with a balanced approach to see how they can best be used," said his spokesman, Dick Skrinjar.

Trail advocates say the resources are there. A recently passed five-year federal transportation spending bill includes $4.5 billion that can be applied to trail construction, among other uses, said Tom Sexton, director of the Northeast Regional Office of the Rails-to-Trails Conservancy.

Over the next five years, the 10-county region can expect around $14 million to $21 million in federal funds that can be used for trails, according to the Southwestern Pennsylvania Commission, which coordinates transportation planning.

The payoff from such investments is intangible, but real, said Mark Bibro, general manager of the Riverwalk Corporate Center. Formerly the Terminal Buildings, the South Side complex uses a nearby trail as a marketing tool, he said.

"The trail brings visibility to our building," Bibro said. "We'll never show the property without showing the trail."

Along with the trails, hiking and biking organizations have sprung up, and they plan to push for more miles even after Murphy's gone.

"The trails have matured to the point where it's almost impossible to ignore them now," said Tom Baxter, interim director of Friends of the Riverfront, which has 4,000 members and counts trails as a priority.

Bike Pittsburgh is organizing both recreational trail users and what it believes to be several hundred bicycling commuters, said David Hoffman, its founding director and now a staff member. "There's really a couple of connections that need to be completed that would make this trail system really world-class," he said.

A trail along the Mon Wharf, which the Riverlife Task Force plans to build next year, would go a long way toward connecting Monongahela River trails with those along the Allegheny. Ramps from trails to the West End Bridge deck -- a longer-term priority of the task force -- would span the Ohio River.

A trail link through Sandcastle Water Park in West Homestead would connect Pittsburgh's network to the Great Allegheny Passage, which will soon run all the way to Washington, D.C. (Kennywood Entertainment, which owns the park, maintains there's not enough room for a trail.)

That combination of city trails linked to regional and national paths would be unique in the eastern states, said Sexton.

Murphy said he considers the trails his proudest achievement as mayor, and a keystone of his legacy.

"You go through Frick Park, you could be in the middle of the Appalachian forest," he said. "Then you have the urban parts. You get this wonderful feel for the fabric of Pittsburgh."