Constellations have been used to navigate for thousands of years, along with compasses, stars guided early civilizations to new lands and allowed them to follow trade routes and reach their desired destinations. Sailors navigating in the Mediterranean made use of several techniques to determine their location, including staying in sight of land and understanding of the winds and their tendencies, as well as watching for certain stars to rise and set which would let sailors know where they were. Some areas also have a long history of using the stars to navigate, Ancient China, for example, had a long tradition of observing celestial phenomena. Nonspecific Chinese star names have been found on bones, dating back to the middle Shang dynasty. These constellations are some of the most important observations of Chinese sky, and it allowed the Chinese to trade and conquer new lands.