El Yunque is the National Rainforest of Puerto Rico, habitat to a diverse group of animals such as the famous coqui and the Puertorrican parrot. There is no admission fee to enter! El Yunque is open all day, but I advice tourists to visit during the day because it is more safe and you will have daylight to see the beauty of the forest. There are many creeks available to step into and swim in, take pictures in, etc. El Yunque is mostly hilly, so expect to hike for most of the day. Parking is available throughout the forest, but spots are not always guaranteed. Parking is free as well!
Bilingual tour guides are available at the Customer center for anyone seeking extensive history on the forest and Puerto Rico. There is also a souvenier shop around the area. El Yunque is a MUST for anyone visting Puerto Rico.