In addition to being a political and economic center for the Maya, Chichen Itza also served as an astronomical and religious center. One of its buildings, El Caracol (literally, "the snail" in Spanish, due to the remains of the circular staircase atop the building) has been discovered to have been used as an astronomical observatory. Although angles of the building mark the sun's extreme positions during winter and summer solstices, others indicate the motion of the planet Venus, which was considered sacred by the Maya. Although much younger than Stonehenge, El Caracol demonstrates the same process of cosmic recordkeeping defined by a stone structure. To build a structure that could precisely define astronomical alignments implies a sophisticated study of engineering and architecture.