This was a wonderful, beautiful walk up, up, up through the canopy - they give you walking sticks as well (which believe me, I'm glad I took one - they really help propel you upwards when walking); lots of hanging bridges of varying sizes that allow you to look straight down into the canopy and above beautiful little waterfalls. The higher you go, the more awesome and greener it gets - there is a cool waterfall/swimming pool at the top that you can swim in (it sucks you in towards the fall on the right side and pushes you out again on the left side - very fun!)
Saw some amphibians (poison dart frogs, eyelash pit viper; lizards; centipedes and other frogs and a beautiful blue dragonfly) If you get there real early you may see some toucans or toucanettes - I think we just missed 'em.
We took the bus from Parrita and arranged for the guide to pick us up from the road (we did the walk on our own though) - if you don't have a car you'll need to do this as it would be too long of a walk to the entrance from the main road; you should probably call in advance to make a reservation for the park anyway.
Park was not crowded at all but for one tour group that came through that we saw at the waterfall pool - we ate lunch here too - food was good and a good deal!
All in all it was a wonderful, memorable day in this very beautiful part of Costa Rica.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.