If you go

Puerto Rico: Bespoke’s El Yunque Rainforest Off the Beaten Path Day Trip costs $85 for children ages 7 to 12 and $95 for those 13 or older (children younger than 7 are prohibited). You don’t have to take a private tour; the National Forest System maintains hiking trails and welcome centers and offers a range of educational activities and nature talks. Access to these trails and recreational areas is free, although parking lots tend to fill up early.

Martinique: Access to the Cap 110 slave memorial is free; tickets for La Savane des Esclaves range from 5 euros, or around $5, for children to 12 euros for adults, with special prices for students and citizens of the island.

Nevis: For visitors to the island, both the Horatio Nelson museum and the Hamilton House charge $5 for adults; children under 12 are admitted for free. The Hamilton House price is expected to increase to $10 (guess why).

Grenada: The informal tours at Crayfish Bay are free; simply show up. The House of Chocolate museum is also free. The make-your-own bar at Tri-island costs $20. Tours at Belmont cost $5.

St. Lucia: Fees to hike Gros Piton start at $50, but expect to pay more for various packages, especially if your hotel organizes your trip. For St. Lucia visitors, Pigeon Island costs $10 for adults and $3 for children ages 5 to 12. Entrance to the botanical gardens is $7 for adults and $3.50 for children; admission to the baths is extra. Tours of Sulphur Springs begin at $100.