Ruta Puuc is a site covering lots of pyramids starting at Uxmal, in the Yucatan. The main ones are Kbah, Sayil, Xlapak and Labná.
You need at least half a day to visit all the pyramids which are strung out along a 48 km road.
After having seen the big pyramids of Chichén Itzá and Uxmal, I discovered the small pyramids of Ruta Puuc. Less touristy, but just as interesting, they are an opportunity to learn more about the Mayan civilization.