Hike in Bear Mountain State Park
Start the hike from bear mountain inn, cross the road and wind through a wild animal preserve, cross the hudson river via the bear mountain bridge, join up with the appalachian trail, then split off to "anthony's nose," a scenic overhang where the entire valley can be viewed. if you do this hike at the end of sept or beginning of oct you may be lucky enough to catch the oktoberfest near the bear mountain inn afterward.
Take a cruise
On the river aboard one of many boats. pride of the hudson, +1 845 220-2120, (http://www.prideofthehuds...) departs from newburgh. commander, +1 845 534-7245, (http://www.commanderboat.com) departs from west haverstraw, west point, and peekskill. rip van winkle, +1 845 340-4700, (http://www.hudsonrivercru...) and teal, +1 845 679-8205, (http://www.northrivercrui...) both depart from kingston.
Take sailing lessons
At the croton sailing school, senasqua rd, croton-on-hudson, +1 800 859-sail, (http://www.crotonsailing.com).
kayak tour
Take a guided kayak tour through the Hudson Highlands: Hudson Valley Outfitters, 63 Main St, Cold Spring, +1 845 265-0221, (http://www.hudsonvalleyou...). Or paddle the entire tidal portion of the river via the Hudson River Water Trail (http://hrwa.org). Join the annual Great Hudson River Paddle (http://hrwa.org/ghrp/inde...) as it wends its way from Albany to New York City.
New York-New Jersey Trail Conference
(http://www.nynjtc.org). join a group hike sponsored by the trail conference. you could also venture off by yourself with a nynjtc topographic trail map to the hudson palisades trails, harriman-bear mountain trails, or the east and west portions of hudson highlands state park.
Watch bald eagles
In winter, the new york department of environmental conservation recommends the following viewing points: riverfront park, peekskill; charles point's china pier, peekskill; george's island park, verplanck, town of cortlandt; constitution island from the north dock at west point; norrie point state park, hyde park; iona island, viewable from the turn-out off route 6 just south of the bear mountain bridge on the east side of the hudson river.
Follow Ichabod Crane's route
(http://www.olddutchburyin...). fans of washington irving's the legend of sleepy hollow can follow the route of ichabod crane from tarrytown to sleepy hollow. but don't expect to find the "western woods" or anything else from the 1999 movie sleepy hollow. tim burton's production is only loosely based on irving's story, and was filmed largely in hertfordshire, england
Rock-climb
In shawagunks the gunks (http://www.mohonkpreserve.org), one of the largest and most accessible cliffs on the east coast. you can buy or rent basic climbing equipment from emc or rock and snow in new paltz.