Rent a rickety bike and cycle through the ruins of ancient Mayan culture.
A short 45 minutes from Tulum, Mexico lies the partially excavated Mayan ruins of Coba. Encompassing 80 square kilometers, ancient Coba was connected via a network of elevated roads called sacbes.
After paying a small entry fee to the Mexico National Institute of Anthropology and History ($64 pesos, $3.50 US) stop by the bike rental station inside the entry gate. For $40 pesos ($2.25 US) you can pick a bike from a fleet of aged mountain bikes. They are all built for those of shorter stature, so consider it part of the adventure and crank up the saddle.
The cycling surface is wide, flat, and reaches all the excavated areas of the park. The main attraction is Nohuch Mul, the highest pyramid in Mayan Mexico and one of the only open for climbing. Nohuch Mul is the also the prime destination of tour groups. It's worth the climb to the top, but the less visited, quieter areas of Coba are where the magic lies.
Coba has limited tourist services. Be sure to pack food, water, sunscreen, bug spray, and clothing appropriate for the season. The temperature will be muggy and hot in most seasons, but the jungle provides ample shade.