Culebrita Lighthouse is the only remaining Spanish-era structure in the Culebra archipelago. Construction of the lighthouse began on September 25, 1882, and was completed on February 25, 1886. The Spanish Crown built the lighthouse to help secure its claim over the main island of Culebra. It is the most eastern light outside mainland Puerto Rico. It guided navigation through the Virgin Passage and the Vieques Sound connecting in the Puerto Rico Light System with the Cape San Juan Light.