After being collected in the morning from your San Juan area hotel, the tour will head west to the town of Arecibo, and to a cave called 'Window Cave'. There you will have a guided tour and learn not only about the cave, but the history of Puerto Rico, its ecosystem, and the aboriginal peoples. From there, on a clear day, you can see the highest peak in Puerto Rico, Cerro Punta, as well as one of it's largest rivers. The overall time there will be approximately 2-hours. There are souvenir kiosks that you may shop after the tour if you wish.
From there, the tour moves to the coast where lies one of the many hidden gems of this island, Indian Cave. There, you'll have some amazing views and plenty of photo opportunities. At the top are some petroglyphs where parts of a few blockbuster movies were filmed! Time there is flexible, but the average is an hour and 15-minutes.
After, you'll go to lunch for some authentic Puerto Rican cuisine, already prepared for you (at own expense). Then head east back to your San Juan accommodation afterward.