Just got back from SP on Friday. Thursday my girlfriend and I went to the main land for the day. Rented a car, and drove to Blue Hole National Park. We hired a guide named Marcos to take us through ST. Hermans Cave and went cave tubing. It was possibly the best thing we did while there. He was great and says that he does tours all over the country, ruins, caves, and even jungle tours. If you don't want to be with a "tour group" but want someone to show you a great trip, I would suggest him. I have his contact info if you want it. Also keep in mind when planning a day trip that if you are going to caves or mayan ruins you have to hire a guide you can't explore them yourself.