4 star rating: Recommended 54 Reviews

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  • Address: PR-625, Arecibo, Puerto Rico 00612
  • Admission: Adults: $10; Students: $6

Puerto Rico ATTRACTIONS See all

Arecibo Observatory Tours

The Arecibo Observatory has earned a reputation as the largest and most sensitive radio telescope in the world. It features the William E. Gordon telescope as well as a visitor and public outreach center and scientific research community. As more than 1,000 feet in size, it is the world’s biggest single aperture telescope. It is known also as the National Astronomy and Ionosphere Center (NAIC) and is run largely by the National Science Foundation. It was constructed in the mid-1960s in the space left in the ground from a karst sinkhole. 

With three radar transmitters, it has the largest electromagnetic-wave-gathering capacity in the world, within a forty-degree cone of visibility. Many breakthroughs and discoveries have been found by scientists from around the world in the facilities here, including the rotation rate of Mercury and evidence that neuron stars exist. The observatory was listed on the American National Register of Historic Places in 2008.

Practical Info

Visitors can learn more about the radio telescope and atmospheric science at the Observatory’s Ángel Ramos Foundation Visitor Center, open Wednesday to Sunday. Admission costs are $10 for adults and $6 for seniors and students. Don’t miss the amazing view from the Observation Deck. Drive there from San Jeuan in just over an hour.

Tours & Tickets

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San Juan Day Trip to Cueva Ventana and Arecibo Observatory, San Juan, null
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 3

San Juan Day Trip to Cueva Ventana and Arecibo Observatory

5 star rating: Highly Recommended 7 Reviews

Important Notice: Due to the damages caused by hurricane Maria (2017) the Camuy Caves will remain closed until further notice.  We have temporarily substituted ...  Read more

Location: San Juan, Puerto Rico
Duration: 9 hours 30 minutes (approx.)

From USD $165.00
North Coast of Puerto Rico from San Juan: Arecibo Observatory and Cueva del Indio, San Juan, Day ... 
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 5

North Coast of Puerto Rico from San Juan: Arecibo Observatory and Cueva del Indio

5 star rating: Highly Recommended 14 Reviews

Explore some of Puerto Rico's highlights on this full-day tour. Visit the Arecibo Observatory, see where Taino Indians spend time at Cueva del Indio and...a ...  Read more

Location: San Juan, Puerto Rico
Duration: Flexible

From USD $111.25
Cueva Ventana and Arecibo Observatory from San Juan, San Juan, Day Trips
TVRM_SORTED : true ESSENTIAL : 1 ADMISSION : 5

Cueva Ventana and Arecibo Observatory from San Juan

4.5 star rating: Recommended 113 Reviews

IMPORTANT NOTE: Camuy Cave is still closed after extensive damage from Hurricane Maria in Sept. 2017. We will instead explore the Cueva Ventana which includes ...  Read more

Location: San Juan, Puerto Rico
Duration: 9 hours (approx.)

From USD $119.00

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