Mount Rainier is a city in Prince George's County, Maryland, United States. The population was 8,080 at the 2010 census.
In 1891, the City of Mount Rainier was named by a group of developers after the famous mountain in the state of Washington. In 1899, the streetcar lines were extended from Washington D.C. through Hyattsville, Maryland. The Mount Rainier stop was located at the intersection of what is now known as Rhode Island Avenue and 34th Street. It was called the District Line Station. With the stop at Mount Rainier, it was easier to attract developers and prospective buyers because now the city offered easy access to get into and out of Washington. Houses started to be built near the District Line Station after 1902. The homes on Mount Rainier were considered affordable, ranging from $2000 to $5000. The business district aggregated around the streetcar station. In addition to the station, there were shops, grocery stores, a barber shop, laundry, and dry good stores. The first post office was established in 1904. In January 1912, the Mount Rainier volunteer fire department was created. The fire department was first located in a frame building and later moved to a brick structure located on 34th at Shepherd St.