Coba occupies an area of approximately 70 square kilometers and was one of the great Maya cities of the classic period. In Maya the word Coba means "waters stirred by the wind" probably because of the five cenotes in this region. In Coba one can see approximately 45 roads known as sacbe (white roads) which connected the city with other places. The ruins were opened to the public in 1973, but only few of the approximately 6000 structures were restored or uncovered. In Tulum most of the buildings belong to the early post-classic period - 900-1200 AD and have a distinct Toltec influence. They are not as impressive as Coba, or other sites but the combination of the ruins and the turquoise sea is simply irrestible.