What trails or roads do you conquer to train for the Leatherman’s Loop (and other trail runs) each year? Please tell us in the comments what you do to train and what trails (if any) you like. There are a number of local preserves close to the Reservation that offer single track and wider trails.
The biggest trail network locally is of course, at the Ward Pound Ridge Reservation itself, home of the Leatherman’s Loop 10k trail race. Check their site for a comprehensive trail map (pdf) of the park.
Note that parts of the Leatherman’s Loop 10k run are not marked trails. The longest unblazed portions include the 1km just before the first stream crossing and the 1km from the water stop on Boutonville Rd through the mud flats along Route 124 joining up with the Deer Hollow trail. This can be confusing if you want to scope out the trail ahead of time and take a few practice Loops. By fall and wintertime, much of the unmarked trail can get overgrown, especially the mudflats. If in doubt, double back!
Also the Leatherman’s Loop 10k run is not close to the trail marked “Leatherman’s Loop” on the official county park map. The trail marked “Leatherman’s Loop” on the county park map is the trail that is used to reach the Leatherman’s Cave. The Leatherman’s Loop 10k trail run is in the northern part of the park while the Leatherman’s Cave Loop is in the southwest part of the park.
Take a look at the map below or check this link to see the loop course traced out by a Garmin 305 GPS unit during the 2008 Loop.
A neat thing about the Google Map is that the current satellite images used were taken a day or so after the 2007 loop. The 500 year old Meadow Oak tree is still standing and you can see the teepee along with Mike and Tony’s trucks getting ready to pack up the supplies. On the mud flats portion of the loop (near route 124 on the right side of the map) you can clearly see the multiple mud trails if you zoom in to the closest setting. 2007 was a sunny loop but the trails were muddy and rain-soaked!
(EDIT: as of 2011 Google updated the satellite photos to more recent shots (2010 summer) and you can no longer see the teepee or truck. I am told that Google Earth has a timeline feature that allows you to look back at previous satellite photos over the same are but I have not tried it.)

In a future article, I will post some 3, 4, and 6-mile trail runs in the Northern Westchester area. Some of the preserves I have run in are the Mountain Lakes Park, the Leon Levy Preserve, Merestead, Butler Sanctuary, Westmoreland Sanctuary, the Meyer Preserve, the Marsh Sanctuary and the Indian Brook/Yarrow/Grierson Preserve. Happy Running/Hiking!
EDIT: check this article summarizing trail run overview to date.