Hi! I'm writing from Costa Maya, if you'd like to set your day for Mayan ruins be advised that there are 3 different Mayan ruins that can be visited from Costa Maya port, and there are 5 different tours that include Mayan Ruins. Pretty much depends on how long you'll like to spend on the tour.
Most popular tour:
Chacchoben Mayan Ruins, 4 hours total time.
Other tours to the same ruins:
Chacchoben Mayan Ruins Exclusive Drive. The tour from start to finish takes only 3.5hours and you're in a small group. Includes refreshments.
Chacchoben Mayan Ruins and the blue lagoon for 6.5 hours this last one includes a buffet at the lagoon.
PROS of Chacchoben short drive (1 hour each way) Souvenirs and Snack shopping possible at the ruins.
CONS of Chacchoben, can't climb all buildings, no carvings neither decorations on walls left. Sometimes can be crowded, depends on the number of cruises in port that day.
The other two Mayan Ruins are Kohunlich and Dzibanche Mayan Ruins, but be advised that these ones are much further away than Chacchoben, because they nearly reach the border between Mexico and Belize.
There is Kohunlich Tour for 6.5 hours and there is the combo visiting Kohunlich and Dzibanche for 8 hours. Neither of these two include a big meal, is just snacks for the ride and a simple sandwich for the way back.
Pros of Kohunlich Only Tour: Easy itinerary, drive, visit, drive back. Plenty of time to explore the ruins, site is big so 2 hours there is the right time. You can climb most buildings, it has a ball game, and it has beautiful carved and stuccoed masks on one temple, everything is original.
CONS, long drive, NOTHING to buy on site because is in the middle o the jungle. Not much time left in port when you go back.
Pros of KOHUNLICH + DZIBANCHE COMBO
Dzibanche has the tallest structures in the area, and guests are allowed to climb all temples, you get to see a great overview of all the Mayan civilization from residences, temples and plazas. Two sites in one day chance is a must do for some people.
Beautiful scenic drive and you get to see the real Mexico in a safe way.
Cons...
This tour will consume all your time in port, you depart to the tour at the ship's docking time, and when you finish the tour, you have to go back to the ship because they're only waiting for you... Check your ship arrival and departure times.
Because of the long drives to and from the ruins and the driving time in between them, you are only given 1hour on each archaeological site, one hour is the right time for Dzibanche, but sometimes an hour may seem short for kohunlich. Well, also you can take into account that by the time you get to the second ruin, you may have already consumed great energy and you won't feel that eager to explore much of the second site.
Only light snacks, water and a sandwich provided, remember it's 8 hours so you may want to bring some food.
Hope this info helps you decide!