At Long Branch, I usually stayed at the Ocean Place hotel. That is a very nice hotel, right on the Atlantic Ocean (as the name suggests). I enjoyed going to sleep with the soothing sounds of the ocean waves.
For running, there is pretty much only one option; the boardwalk. That is a nice route although not very long. It goes along the ocean (obviously), there is no traffic and the air is fresh (well, New Jersey fresh). I would usually go south from the hotel, then back. To the south, the boardwalk goes to Brighton Avenue and to the north, it only goes to Seaview Avenue.
On the day I recorded this, I went for the total of 3 miles at 7 min 20 second per mile. That is really a minimum distance for it to qualify as a run. Anything shorter than that is a warm-up.