No, not an ultramarathon! The Westchester Trails Association has put together “The Westchester 100.” Best described at the WTA website: “It is a project inspired by the publication of the “Walkable Westchester” book by Jane and Walt Daniels. We’ve compiled a list of almost all the hiking areas and trails mentioned in the book, and are sponsoring guided hikes to 99 of these locations. Hike No. 100 is to one or more mystery locations which are not referenced in the book.” After you complete 50 of the 100 you can write to them and get a certificate. After you finish 99 of the 100 they reveal the mystery trail to you.
More information about the Westchester 100 can be found at the “News and Notices” page of the WTA website here: http://westhike.org/News_and_Notices.html A list of the trails and parks in the 100 is here: http://westhike.org/uploads/Westchester_100__website_.pdf (PDF file). More information is here: http://www.nynjtc.org/content/hike-all-trails-westchester-county
There is also a list of hikes to give you a flavor for the book: http://www.nynjtc.org/content/suggested-hikes-walkable-westchester
For those in NJ there is a searchable database of trails in the NY/NJ area here: http://www.nynjtc.org/view/hike
Thanks to the New York New Jersey Trail Conference (http://www.nynjtc.org) and the Westchester Trail Association (http://westhike.org) for putting all of this together. If you love trails, support these organizations!