Exploration of the Moon invention of the telescope, an increasing number of people began to recognise the Moon as a sphere, though many believed that it was "perfectly smooth". In 1609, Galileo Galilei drew one of the first telescopic drawings of the Moon in his book and noted that it was not smooth but had mountains and craters. Later in the 17th century, Giovanni Battista Riccioli and Francesco Maria Grimaldi drew a map of the Moon and gave many craters the names they still have today. On maps, the dark parts of the Moon's surface were called "maria" (singular "mare") or seas, and the
Craters of the Moon National Monument and Preserve available in the Craters of the Moon Wilderness and the much larger Backcountry Area beyond (added in 2000). Only two trails enter the wilderness area and even those stop after a few miles or kilometers. From there most hikers follow the Great Rift and explore its series of seldom-visited volcanic features. All overnight backcountry hikes require registration with a ranger. No drinking water is available in the backcountry and the dry climate quickly dehydrates hikers. Avoiding summer heat and winter cold are therefore recommended by rangers. Pets, camp fires, and all mechanized vehicles, including bicycles, are not allowed in the