There are few places to stay near Calakmul. The closest accomodations
are at the Ramada Chicanna Ecovillage (across highway 186 from the archaeological
zone of Chicanna). The cost is pricy ($70-90 USD per night) but well worth
the splurge. I also recommend the Ramada Chicanna as a great homebase for
exploring the nearby sites of Xpujil, Chicanna, Becan, Hormiguero, and
Alternative places to look for rooms include the town of Xpujil, which
has cheap places to swing a hammock, and the cities of Escarcega and Chetumal.
Just remember that the further you are from the center of the peninsula,
the less time you will be able to spend exploring Calakmul.