The arched ceiling drips like a leaky dam. Cracks riddle the brickwork, which sags overhead like a clay guillotine as we crawl through the belly of one of Richmond's greatest legends, the Church Hill tunnel.

A portion of Jefferson Park above the tunnel - near the buried train - gave way in 1962. A decade ago, the 16-foot-thick snake kinked its back below 29th Street, swallowed a tennis court and may have helped tip two houses. And earlier this year, an old brick pharmacy almost directly above the East Marshall Street portion of the tunnel was torn down after one of its walls fell into the street, although the city's building inspector doubts the tunnel had anything to do with it.