One of the 7 modern wonders of the world, this site is overflowing with visitors and vendors. We rented a car and it was a 3 hour drive from Playa Del Carmen. When we arrived at 1015, the parking lot was not full but it was full in the afternoon.
The pyramid is the main attraction but not the only one. Do not miss the two Cenotes, the big arena of Ullamaliztli(Aztec ball game) and the excellent temple of warriors.
I am giving this site 4 star because there are way too many vendors selling the same things. While the souvenirs look good, the constant hissing sounds from a toy, constant clapping by tour guides and other tourists dulls the experience a bit.
We spent four hours here including a very good lunch followed by a visit to the beautiful cenote nearby.