Riverdale Park is known for its spectacular views of the Hudson River and the Palisades, but it’s also a haven for birds, with at least 27 species confirmed breeding there. See how many you can spot today on the Birding and Riverwalk Hike, organized by the Urban Park Rangers. A geological wonder, the 50-acre park sits on the oldest rock formation in New York, the billion-year-old Fordham metamorphic rock, which is topped by Inwood marble. Also, look for the oak trees—at least five varieties thrive here—and the southernmost parts of the park are still the same type of forest that existed pre-colonial, including 110-feet tulip trees. With the weather turning in our favor, this is a glorious opportunity for exercise and bird watching—if you have binoculars, don’t forget them.

Sat., March 12, 1 p.m., 2011