picture1 of 2
2 of 2
IsaacRuiz/Getty Images

Key Info

Route 625 Bo. Esperanza


Museums Type


  • 4.0Value
  • 3.0Facilities
  • 4.0Atmosphere

Since the 1960s, scientists have used Arecibo Observatory's massive telescope to collect data about Earth's atmosphere, the solar system's planets, comets and more. Though Puerto Rico may seem like an odd place for this important device, it's actually the perfect location. Situated near the equator, the telescope is in the ideal spot not only to study the Earth's ionosphere (its original purpose) but also to study planets. In addition, Puerto Rico could accommodate the space needed for the telescope's reflecting mirror: The dish is 1,000 feet in diameter and 167 feet deep.

Visitors can indulge their scientific curiosity at the site's Science & Visitor Center. There, they can view exhibits about atmospheric science, attend lectures, watch informative movies and visit the observation deck to see the telescope and its radio mirror. There is also a gift shop on-site.

Past travelers said the observatory is a must-see attraction in Puerto Rico. They cautioned that the museum is small, but is a great place to take kids. In addition, past tourists recommended taking the guided VIP tour to gain access to behind-the-scenes sights like the warehouse and engineering offices. A few reviewers bemoaned the hike to the observatory. There is a steep climb with many stairs from the parking lot to the Science & Visitor Center; however, transportation is available to the top.

The center is located in Arecibo, approximately 60 miles southwest of San Juan and 45 miles east of Rincon. It's also about 10 miles southwest of Cueva Ventana; combining the two would make a great daytrip. Many past tourists recommend driving to the site yourself but warn of winding roads. The Science & Visitor Center is open from 10 a.m. to 3 p.m. Wednesday through Sunday. Tickets cost $12 for adults and $8 for children ages 5 to 12; the VIP tour will cost extra. Visit the observatory's website for more information.

See all Hotels in Puerto Rico »

More Best Things To Do in Puerto Rico

1 of 18
2 of 18
Time to Spend
#1 Bioluminescent Mosquito Bay (Vieques)

This south Vieques beach might not sound like much, but it's one of travelers' favorite experiences in Puerto Rico. During the day, Bioluminescent Mosquito Bay is your stereotypical Caribbean hideout but at night, the waters emit a blue glow from the organisms, called dinoflagellates, that live there. More than 600,000 bioluminescent dinoflagellates live in each gallon of bay water, and recent travelers have been amazed by just how much visibility these tiny creatures provide.

Avoid visiting the bay during a full moon; the microorganisms aren't as visible then. Also aim for a quiet approach. Recent travelers recommended going out in a kayak to get the full effect of the glow and to prevent disturbing the dinoflagellates.

Read more
Todd Van Hoosear/Flickr
See full list of Best Things To Do in Puerto Rico »

Explore More of Puerto Rico

If you make a purchase from our site, we may earn a commission. This does not affect the quality or independence of our editorial content.