With J., rode the sections of the Putnam County (NY) Trailway between the current northern trailhead at Tilly Foster Rd., and the village of Mahopac. The trail is nicer than I expected, with interesting sections following old rail routes, especially on an old railroad bridge crossing Middle Branch Reservoir and through a lot of fairly deep woods. The trail goes through countryside that is not quite as pristine as the Amenia bike trail, but OTOH this was a much bigger engineering effort, with many bike-only tunnels and bridges. We turned around and retraced our steps when we got to Mahopac (the trail actually continues deep into Westchester County), stopping after for a fine frappucino in Carmel.
For some reason (I think because Google Maps' biking maps don't support it yet) this map can't be embedded, but here's the link.
In case you are all wondering why the frequency of rides is much lower than this time last year, it's for two reasons: 1) playing a lot of frisbee at what otherwise would be good bike times, 2) opportunities are scarcer because I'm working hard on my phd to try to finish it this year.