Barro Colorado Island

When the Chagres was dammed in 1913 and Gatun Lake filled, a hill became an island of about fifteen square kilometres, and in 1923 it was set aside as a reserve. The Smithsonian Tropical Research Institute has run it since 1946, and the result is a forest that has been watched continuously for a century: every tree above a certain diameter in a fifty-hectare plot is mapped and remeasured every five years, a method now copied at dozens of sites worldwide. Day visits run a few days a week with a guide on the trail network, and the point is less the wildlife than seeing science being done in the middle of a lake.

What you actually see

• The fifty-hectare plot - the mapped forest census copied around the world.
• The trail network - guided walks through century-old protected forest.
• The lake crossing - past Panamax ships on the canal channel.
• Howlers and coatis - abundant and unbothered on the island.

When to go

December to April is the dry season. Visits run on a limited number of days each week and places are few, so book weeks ahead through the research institute. The boat leaves early from Gamboa and the day ends mid-afternoon.

Honest expectations

Places are genuinely limited and sell out; walk-ups are impossible. It is a working research station and the visit is structured around that rather than around visitors. The trail is muddy and humid. Wildlife is heard more than seen, as in any lowland forest.

Nearby

Gamboa is the departure point; Soberanía and Pipeline Road are nearby.