instructors hold court, and the roller disco circle throbs. There is no swath of nature more democratically enjoyed, or as vital, in the country. Beside the African drumming circle, the Iranians playing soccer, the Korean wedding, and the thousands of scantily-clad youth sprawled across Sheep’s Meadow, there is the greatest rollerskiing loop in the world! If you have ever watched or participated in the world’s largest road race, the New York City Marathon (or the...