Longmont is a Home Rule Municipality in Boulder and Weld counties in the U.S. state of Colorado. Longmont is located in Northern Colorado. Longmont is the 13th most populous city in the State of Colorado. The word "Longmont" comes from Longs Peak, a prominent mountain named for explorer Stephen H. Long that is clearly visible from Longmont, and "mont" from the French word for mountain. The city is located northeast of the county seat of Boulder and 31 miles (50 km) north-northwest of the Colorado State Capitol in Denver. In contrast to its better-known neighbor, Longmont has a much more quiet and residential feel, although the city has begun to grow rapidly in recent years. The population was 86,270 at the 2010 census.

Also notable, Longmont was declared an "All-America City" by the National Civic League in June 2006. The city was also named number 50 on the 2008 list of the top 100 places to live in the United States by Money Magazine.

Longmont Potion Castle (born 1972 or 1973) is the pseudonym of an anonymous surrealist prank caller who has been active in the Colorado and Los Angeles areas since 1987. Details about his personal life are scarce and his real name is unknown to the public. Over the years, his mostly self-released albums have gained a cult following, notably amongst musicians.

The LA Record describes Longmont Potion Castle's albums as unlike those that most people associate with prank telephone calls, citing that his demeanor is nothing at all like that of The Jerky Boys and Crank Yankers and is actually closer to that of the alternative comedian Neil Hamburger. The magazine goes on to cite some of the topics discussed and parties dialed in the artist's calls: "peacock bowel, owl bowel, peacock meat, squid meat, gorilla ointment, Nugent, Orange Julius, biblioduwangus, woven bread, moving rope and cords into another state, pleated clothing, the Epiphone Dolphin, pumpkin brew, GG Allin, UPS, and opportunities to engender a coalition with the Vatican." In a review from the Denver Westword, LPC's recordings are described as advancing "absurdity as an art form."