There are actually several, just blocks apart. One is at the Southeast corner of 5th Avenue and 9th St. The other is at 14 West 10th street. Legend has it that the 10th street property is haunted, but reports of Twain's ghostly doings have been greatly exaggerated. We've never seen the Twain collection in the NY Public Library, but you'll want to visit that in any case. Enjoy! Terry Ballard Quinnipiac University