Visit Lyndhurst Mansion in Tarrytown

Lyndhurst Mansion is around a 45 minutes train ride on Metro-North from Grand Central Station.  Off-peak roundtrip train tickets will cost around $21.  A quick taxi ride from the Tarrytown train station to the mansion entrance is $7.  A one hour small group guided tour of the mansion is $18.  While this day trip upstate will cost you around $50, I would recommend it for the architectural and New York history as well as just walking around the grounds and taking pictures.