Gillette is now "Energy Capital of the Nation," boasts the local convention and visitors bureau, but just a century ago it was a huge sea of open range. Where there were once herds of cattle, you can now see several massive surface coal mines, like the RAG Coal West-Eagle Butte Mine. The mine, which opened in 1978, shipped its 250-millionth ton of coal on April 15, 1998. The huge coal mines, along with recently discovered coalbed methane gas, have made Gillette a prosperous community, which means that this is a very pleasant place to live (or visit), with a variety of modern facilities, including a first-class swimming pool and water park. There is still plenty of undeveloped plains habitat, too, particularly in the 1.8-million-acre Thunder Basin National Grassland. Anyone who likes geological wonders, and anyone who enjoyed Close Encounters of the Third Kind, will want to visit the nearby Devils Tower National Monument.