OR borrow one of your gracious hosts' and ride it!
This makes so much sense when going to the beach or into town. Cars give bicyclists the right of way, they're so much easier to park, you can get some exercise, AND you'll be so much kinder to the environment!
It took me 2 hours and 15 minutes to get to Rehoboth Beach from Philadelphia. I took I-95 South through Wilmington, Delaware and then hooked up with Route 1 South all the way to the beach. Rehoboth is about 2 1/2 hours from Washington D.C., about the same from Baltimore and about 1 hour and 45 minutes from Wilmington.
Four to six people can hop on one of these. Some have a back seat that faces out. Four people have to pedal at the same time. No bikes on the boards after 10 am in season.
Takes you to a few (and I mean few) select spots. Narrated tours of 6 or more available. From 8am to 2am daily. Map and schedule available on web site.