A few drugs helped me over this morning's “indisposed” feeling (it's amazing what you can get over the counter here), so we acted on our plan for the day, and rented a car.
We drove around the island, or around the part that is paved, at least, which was probably 20-30 miles. We stopped at a couple points to take pictures, and at San Gervasio in the middle of the island (just off the appropriately-named “cross-island road”) where there is a Mayan ruins site.
We spent about an hour poking around the ruins, which aren't nearly as impressive as those at Chichen Itza, but had interesting history. Apparently the site was a major destination for religious pilgrimages during Mayan times, giving the island an over 800 year history of being a tourist trap. If it ain't broke, don't fix it.
We're having dinner tonight at Prima's, which serves northern Italian food, then heading to the airport tomorrow morning for our return flights.