On our last day in Puerto Rico we packed up our stuff, shoved it in the car, and took off for El Yunque National Forest for a few hours before we hopped on a plane to New York. We were a little nervous about timing, and weren't sure that we could fit in El Yunque after a drive across the island, but we did and it was well worth it!
El Yunque is the only tropical rainforest in the United States and it is more lush than you could even imagine! The weird thing is how well maintained the national forest is. It has a lot of paved and dirt trails that allow you to really get into the forest.