Hackettstown is one hour west of New York City by car. A little closer to the east is Metro New York, where one ofhe highlights is historic Morristown, New Jersey.
Heading due West on Route 80, you will reach the Poconos in about half an hour. Route 80 goes on an on all the way past Pittsburgh, Chicago, Des Moines, Salt Lake City and on to San Francisco. To the southwest is the Lehigh Valley in Northeastern Pennsylvania.
The best way to get to the Jersey Shore is to take Route 80 or Route 206 to Route 287, and then keep going south to either the New Jersey Turnpike or the Garden State Parkway.
Philadelphia can be reached that way, but some people prefer to go out to the Lehigh Valley on Route 78, or Route 22, and then to the Northeast Extension of the Pennsylvania Turnpike, S/I 476 South. Definitely consult a good map, though.