Caribbean - Punta Cana Day(or Partial-Day) Activities

Will soon be spending a week at a resort in Punta Cana. I'm sure they'll have an activities desk but would like an idea from my Flyertalk cohorts on fun stuff to do nearby to Punta Cana if sitting on the beach or in the pool becomes too boring. ;)

you will find the resort to be very nice and you will be advised that you shouldn;t leave the property or security reasons,,they are very poor and leave jewelry at hotel i you do go,,we did leave 3 years ago for 4 wheeler and horseback ride and was a little uncomfortable feeling but all ok but since haitis problems on other side of island i would probabley not do it now

I am off to Dreams La Romana in July for 2 weeks after hearing excellent reviews. Apparently there is plenty to do in the resort so don't worry leaving it unless you are going on a snorkelling/boat trip! La Romana is meant to be a lot quieter than Punta Cana, but it is a 1h30min drive from Punta Cana airport! :(

I just hope the weather is good!