The National Park of Manuel Antonio has several trails you can follow. The visit to the park will take you one day, at least. If you enjoy the visit, you can stay more days, and relax on its beaches after, or before, the exploration of its trails.
There is an entrance ticket to access the park. The price is the same as the other National Parks in Costa Rica. You can pay in US dollars, or in local currency (colones).
In the picture you can see one of the iguanas that you will see during a visit to the park.