You can drive all the way around the island and you may wish to stop and look at the few small Mayan ruins on the island. The North shore is beautiful with many small private beaches. Swimming is very dangerous there and you should not do it! Currents are way too strong. You can stop at the Chaknabb Lagoon and swim there and see the fish and walk among the gardens with lots of igunas (big ones too!) You can also drive and park downtown and do plenty of shopping as well as various smaller locations all over the island where you can usually get a much better deal!