The railroad has been consistently billed as one of Disneyland's top attractions, requiring a C ticket to ride when A, B, and C tickets were introduced in 1955, a D ticket to ride when those were introduced in 1956, and an E ticket to ride when those were introduced in 1959. The use of E tickets stood until a pay-one-price admission system was introduced in 1982. With an estimated 6.6 million passengers each year, the DRR has become one of the world's most popular steam-powered railroads.