You for sure want to do an excursion there. Don't wander around! Not the best place to be on your own.
Not sure what the excursion would be called, but we took a long boat ride up the river. Saw lots of wild life. Then they stop for a lunch where they fed you. Very good! They had a few tables set up of stuff you can buy. Then you board a bus to see some ruins.
If I went again, I'd do the cave tubing.