The Isle of Youth: the Cuban island with 56 dive sites, the prison where Fidel Castro was held and caves with pre-Columbian drawings

Rubén Cortada turned 42 on 6 October, at a good moment in his career. Spanish audiences are once again watching him as Ramiro Arribas in "Sira", the sequel to the series "The Time in Between", again alongside Adriana Ugarte, which premiered a few days ago at the San Sebastián Film Festival. Cortada says that during the first series they even asked author María Dueñas for permission to kill Ramiro off, but the second novel changed his fate: "What closer enemy than Ramiro for this second season? I can't imagine another villain."

But the actor who built his career in Spain has one place he always returns to. It's not Madrid, and it's not Havana. It's the Isle of Youth (Isla de la Juventud) in Cuba, where he was born and spent his childhood - where he played tennis and where he first got interested in acting. An island few people outside Cuba know about.

Second largest, yet almost unknown

It lies south of Cuba's main island, separated from it by the Gulf of Batabanó, and is the second largest in the Cuban archipelago. For centuries it was called the Isle of Pines (Isla de Pinos) - a name it kept until 1978. Its relative isolation has preserved its nature: across some 2,400 square kilometres, low mountains, pine forests, marshes, mangroves, caves, reefs and beaches alternate, still far from the big Caribbean tourist routes.

One of the places Cortada especially remembers is the Hotel Colony on the west coast. Nearby is the Punta Francés Nature Park, one of the best places in Cuba for diving. Between Punta Pedernales and Punta Francés there are 56 dive sites - coral walls, gorgonians, sponges, caves, passages and underwater tunnels. On land, there are kilometres of almost untouched coastline and pale-sand beaches surrounded by greenery.

A prison, a revolution and a young Martí

The island also has an unexpected history. Near Nueva Gerona, the quiet little capital, stands the Presidio Modelo - a huge prison built in the 1920s on the panopticon model, with circular cell blocks and a central watchtower. Many political prisoners passed through it, and after the attack on the Moncada barracks, so did Fidel Castro and other Cuban revolutionaries. Nearby is the El Abra estate, where a very young José Martí was interned in 1870 before leaving for Spain; today it's a museum. Inland lies Jones's Jungle, a botanical garden founded in the early 20th century with plants brought from all over the world.

A prison that once held the man who would later run the country - the Balkans know that irony of history well. How many cells in the region remember the people who later sat down in the armchairs of power?

Marshes, caves and drawings of the sun

The further south you go, the wilder it gets. The Lanier Swamp is a natural border between the island's two halves, and beyond it begin forests, mangroves and protected areas. Hidden on the south-east coast are the Punta del Este caves, declared a national monument and one of the most important sites of pre-Columbian rock art in Cuba. Their drawings, some made of concentric circles, are linked to observing the sun and the passing of time.

And the beaches are a story in themselves. In the north they're small, with dark or greyish sand, while in the south long strips of white sand stretch in front of coral seabeds, as at Punta Francés. Further east, in the Los Canarreos archipelago, is Cayo Largo del Sur - another paradise of white sand and clear water, with the Sirena, Paraíso and Blanca beaches and spots where sea turtles lay their eggs. Enough to understand why Cortada, after so many years away from Cuba, comes home precisely here.