Isla de la Juventud (Spanish pronunciation: [ˈisla ðe la xuβenˈtuð]; English: Isle of Youth) is the second-largest Cuban island (after Cuba's mainland) and the seventh-largest island in the West Indies (after mainland Cuba itself, Hispaniola, Jamaica, Puerto Rico, Trinidad, and Andros Island). The island was called the Isle of Pines (Spanish: Isla de Pinos) until 1978. It has an area 2,200 km² (850 sq mi) and is 50 km (31 mi) south of the island of Cuba, across the Gulf of Batabanó. The island lies almost directly south of Havana and Pinar del Río and is a Special Municipality (2,419 km² (934 sq mi)), not part of any province and is therefore administered directly by the central government of Cuba. The island has only one municipality, also named Isla de la Juventud.

The largest of the 350 islands in the Canarreos Archipelago (Archipiélago de los Canarreos), the island had an estimated population of 83,544 in 2019. The capital and largest city is Nueva Gerona in the north, and the second largest and oldest city is Santa Fe in the interior. Other communities include Columbia, La Demajagua (formerly Santa Bárbara), Mac Kinley, Cuchilla Alta, Punta del Este, Sierra de Caballos and Sierra de Casas.^{[citation needed]}

Little is known of the pre-Columbian history of the island, though a cave complex near the Punta del Este beach preserves 235 ancient drawings made by the native population, the Guanahatabey. The first written mention of these drawings comes from French traveller Charles Berchon. The caves were collectively designed as National monument in 1979.

The island was first sighted by Europeans in 1494 during Christopher Columbus's second voyage to the New World. Columbus named the island La Evangelista, claiming it for Spain. The island was also known, at various points in its history, as Isla de Cotorras (Isle of Parrots) and Isla de Tesoros (Treasure Island).

Pirate activity in and around the area left its trace in English literature; notably, Treasure Island by Robert Louis Stevenson, and Peter Pan by J. M. Barrie, each drawing on accounts of the island and its native and pirate inhabitants, by reflecting the long dugout canoes that both pirates and the indigenous peoples used, and the American crocodile (Crocodylus acutus).

Following its defeat in the Spanish–American War and the Cuban War of Independence, Spain dropped all claims to Cuba under the terms of the 1898 Treaty of Paris. The Platt Amendment of 1901, which defined Cuba's boundaries for the purposes of U.S. authorities, left the U.S. position on sovereignty over the then Isla de Pinos undetermined. This led to competing claims to the island by the United States and Cuba. In 1907, the U.S. Supreme Court decided, in Pearcy v. Stranahan, that control of the island was a political decision, not a judicial one. In 1916, a pamphlet titled Isle of Pines: American or What? called for the U.S. to annex or purchase the island to settle the issue.

In 1903, Cuba and the United States negotiated and signed the Hay-Quesada Treaty, which recognized Cuba's sovereignty over the island. The U.S. Senate ratified this agreement on March 13, 1925, over the objections of some four hundred United States citizens and companies, who owned or controlled about 95% of the island's land.

Prior to 1976, the island was part of La Habana Province. With the political and administrative reorganization of Cuban provinces in 1976, the island was given the status of "special municipality"; it is administratively equivalent to a province.