The Tulum tour takes a minimum of 6.5 hours depending on the cruise line. There is a 35min minimum ride to Playa del Carmen, another 10minute walk to get to the buses, a 1h ride to the ruins ...which are beautiful and breathtaking. I recommend that if this is your interest or you are coming to Cozumel (or planning to come) on several occasions...this is a must do, just very impressive. They roped off the stairs of those ruins many years ago and also Chichen Itza it now roped off, just a small hand of ruins still can be climed such as Coba and Muyil..until Costa Maya is open again also Chacchobben...or try the San Gervasio Ruins in Cozumel, small but charming and takes only little time to get an insight into the Mayan culture. Good luck!