Reach Punta Allen from Tulum is such a thing! Took 3 hours and a 4×4 car to drive 50km of gravel road, but it was totally worth it. The only way to get there by land is passing trough the biosphere of Sian Kaan. You will drive with the ocean on your left and the lagoon on the right.
Part of the reason of such a long trip is that you can’t resist to stop your car every 10 minutes, to admire the landscape. The town of Punta Allen looks like a ghost town. It has all the services (school, playground, library and police station) and just few people.
We loved it!