The main activity in the island is certainly hiking, there are around 217 trails. Other than that you can also do water activities like kayaking, snorkeling, or guided tours.
Water:
Yani excursions
Excursions Tina
Speedy Adventure
Ocean Whale Watching La Gomera
Amazonia
Gomeractiva
Land:
Bike Station Gomera
Timah Trekking
Bikers Inn – Best Bikes and more
Gomeractiva
If you want to visit Alto de Garajonay and the forest, we highly recommend Route 18 (it starts at the “Pajaritos” bus stop).