El Yunque, (also the name of the tallest peak in the forest), is the only tropical rain forest in the United States. The area receives 200" rain each year, but it didn't rain the day we were there.
There are huge trees, vines, ferns, moss, and impatients blooming by the thousands. Numerous streams run down the mountainsides making waterfalls and pools.
Don't miss the visitor center, El Portal, at the entrance. There are many displays, a short film in English and Spanish explaining the forest, restrooms, and a gift shop. There is also a nature trail with plants labeled. The breadfruit tree was one interesting plant along the boardwalk--also orchids growing.
Near the main road is La Coca Falls. Park your car and get out to crawl on the rocks up to the rock wall with water streaming down. Take a look over the edge of the bridge on the other side to see the water continue its tumble down.
The Yokahu Observation Tower offers a magnificent view of the forest and the whole northeastern coast of Puerto Rico. Lots of stairs here, but worth it.
Farther into the park you will find a trail to La Mina Falls. This is .8 mile of fairly rigorous hiking. The trail has a number of stairs so it's not good for wheelchairs or strollers. The falls are beautiful, and there is a large pool to frolic in--if you can take the cold water! I was suprised to find such cold water in the tropics! Begin your hike early to avoid the crowds that arrive in the afternoon.
We didn't see or hear any coquis, but I'm told they only come out at night or after a rain.
There are several concession stands along the road. Longer hiking trails lead up the mountains if you have more time. We spent 4 hours here and didn't have time to do the longer trails.