Cog railways have been constructed in mountainous areas or mining operations. Cog railways, also called rack railways, were built to climb mountains using a unique toothed rack rail. The Mount Washington Cog Railway in New Hampshire was the first use of this technology in the United States. There are also currently about 50 rack railways throughout the world. The Mount Washington Railway Company or, more familiarly, the Cog Railway, or simply “the Cog,” was chartered by the New Hampshire State Legislature in 1858. Thankfully these railroads are now historical landmarks.