Hopefully you’ll have a car, anything worth doing will be in a surrounding town or off of route 22. Watchung itself doesn’t have a true downtown and is mostly hilly roads with no sidewalks and lots of trees. Summit and Westfield are cute towns close by where you can walk around downtown and ogle beautiful houses. As others have suggested, walking through the Watchung Reservation and Feltville is also a good time. If you’re into local theater, The Papermill Playhouse in Millburn is doing The Sound of Music. And if all else fail, hop on the train and go into NYC.