Bicycling across the Birmingham Bridge to the South Side one pre-dawn morning, Bob Regan saw two strings of lights climbing the dark slope ahead.

They drew him as surely as they would a moth. Regan rode to them, knowing they were illuminating city steps, and then rode home to Squirrel Hill to share a revelation with his wife, Shirl.

"I woke her and said, 'I'm taking three months off,' " he recalled. "She said, 'OK,' rolled over and went back to sleep."

That was the spring of 1999. Regan had become obsessed with Pittsburgh's steps within a couple of days of his arrival in Pittsburgh in 1992, but it took seven years of procrastination and one morning of inspiration for him to take them on as a project.

Once he did, this computer expert who can't type, this 64-year-old who puts more than 2,000 miles on his bicycle each year, rolled through the greatest three months of his life. No boss to whom to answer, no deadlines save his own, he biked Pittsburgh neighborhood by neighborhood, from 5 a.m. to mid-morning, from late May into August.

The result is a paperback book, "The Steps of Pittsburgh: Portrait of a City," chronicling nearly 45,000 steps stacked in more than 700 sets and scattered among 66 of Pittsburgh's 90 neighborhoods. Regan has climbed most of them and mapped virtually all of them. (He found three or four more sets this spring.)

We didn't take any of the book's climbing tours, but we did drive to Murrysville, of all stepless places, because a fourth-grade class at Heritage Elementary School had completed a report offering ways to save Pittsburgh's vertical heritage. (Suburbanites dreaming up ways to save the city seems to be the theme of 2004).

As we drove east, Regan told me he'd grown up on the route of the Boston Marathon, and that he witnessed the Pittsburgh Marathon one of his first weekends here. He thought it a poor copy. A city should celebrate something uniquely its own, so why not the greatest collection of steps in America?

The children in Marcy Canterna's class would agree. When this bearded man in shorts walked into their classroom, he expected to give a presentation, but Regan instead stood in awe and watched the students present a report so concise and jargon-free it was clear that no paid consultant had come near it.

A city that's closing fire stations and postponing street paving hasn't the scratch to do much with steps. But the students suggested that neighborhoods adopt the steps, that they hold step parties and line the steps with carolers at Christmastime, that they hold fund-raisers to save our most healthy and nonpolluting form of transit. (And the views beat anything on any health club TV.)

Some of that is already happening, with the Fineview Step-a-thon and Step Trek on the South Side Slopes, but many a set of steps is overgrown with weeds and crumbling.

"Will you take the presentation to the [City] Council?" student Luke Sciulli asked.

"Absolutely," Regan told him. "They may throw me out, but I'm taking it."

Canterna, who is writing a study guide to go with Regan's book, said she wanted to teach her children how to change a social problem by using research to back their opinions.

"I am amazed at their enthusiasm for this project, especially this late in the school year," she said.

Well, Tim Fabian's photo on page 45 of the Steps book, of bicycle cop Matt Marks riding down the steps of Worth Street in Squirrel Hill, didn't hurt. That looked way cool. Regan fielded several questions on that maneuver, one that definitely fell into the category of don't try this at home.

Regan was genuinely touched by the show of support, and not just because "this is the longest time I've been in school without getting in trouble." Of the steps, he told the children, "They're some of my best friends. They felt ignored. They felt like the city had forgotten them. They felt abandoned."

No more.