"Natural Bridges National Monument was named the world's first International Dark Sky Park in 2007 ... Owachomo is the smallest and thinnest of the three natural bridges here and is commonly thought to be the oldest. We may never know for certain, because each of the bridges is eroding at different rates. Owachomo means "rock mound" in Hopi and is named after the rock formation on top of the east end of the bridge. Before William Douglas gave it this name in 1908, it was called "Edwin" or "Little" Bridge.
NPS - Jacob W. Frank