Peekskill ending:

Peekskill RR Station (start) > Rt 6 > Albany Post Rd > Canopus Hollow > Peekskill Hollow > Rt 301 > White Pond > Rt 55 > Rt 216 > E Hook Cross > Hosner Mtn > Farmers Mills > Rt 301 > Peekskill Hollow > Oregon Rd > Peekskill RR Station (finish)

(GPS link further below)

Southeast ending: 

Peekskill Metro North station (start)> Sprout Brook Rd> Canopus Hollow Rd> Peekskill Hollow Rd> Nimham Rd> 301> Gipsy Trail> Leestown Rd> Hosner Mtn Rd> Rushmore Rd> Shenandoah Rd> lunch> Townsend Rd> Hosner Mtn Rd> 52> 216> 55> Grape Hollow Rd> Mtn Top Rd> 52> White Pond Rd> Farmers Mills Rd> Horsepound Rd> 52> 311> 164> Farm to Market Rd> Southeast Metro North station (end)

http://ridewithgps.com/routes/7256418 route with southeast ending