Pluto is located in a region of the solar system known as the Kuiper Belt. The Kuiper Belt is an area beyond the orbit of Neptune, filled with a vast number of small, icy bodies that are remnants from the solar system's formation. This region is similar to the asteroid belt but is far larger, extending from about 30 astronomical units (AU) from the Sun out to about 50 AU. Pluto is one of the most well-known objects in this region and was considered the ninth planet in our solar system until 2006 when it was reclassified as a "dwarf planet."