Chichén Itzá

El Castillo Chichén Itzá (here by Matija Grguric) was a Mayan temple to the feathred snake deity Kukulkan. Interestingly, at the spring and fall equinoxes the temple casts a snake-like shadow along the northern stairs, showing that in addition to being the site of sacrifices and other ceremonies, this temple helped mark the calendar. Another aspect in this regard is that the temple has 365 steps (91 on each side plus the top).