Which monorail used to begin the monorail that is a 3.9 mile long monorail mass transit system?
Mark IV monorail The Mark IV monorail was a design model of straddle-type monorail trains. The design was developed by legendary Disney Imagineer Bob Gurr. Ten trains were built by Martin Marietta in 1969 at the cost of about $7 million USD each and they were used on the Walt Disney World Monorail System between 1971 and 1989 before they were replaced by the Mark VI monorail, although a few lasted until 1991. Sometime between 1991 and 1994 Monorail Coral and Lime (which had been introduced new in 1984) were sold for $3.5 million each, refurbished, and used to begin the Las Vegas Monorail operations. In 2004 Lime and Coral (now the MGM and Bally) were replaced by fully automated Bombardier MVI 4-car trains.
IRT Third Avenue Line The IRT Third Avenue Line, commonly known as the Third Avenue El and the Bronx El, was an elevated railway in Manhattan and the Bronx, New York City. Originally operated by the New York Elevated Railway, an independent railway company, it was acquired by the Interborough Rapid Transit Company (IRT) and eventually became part of the New York City subway system.