3801 Ltd was established in 1985 and operates as a not for profit company. They are a heritage and tourist train operator, operating The Cockatoo Run and The Illawarra Tree Top Flyer between Sydney and the Illawarra escapement, as well as regular regional tours.

3801 Ltd also regularly visits Maitland Steamfest; in 2009 they operated a triple headed steam service, featuring locomotives 3830, 3237 and 5917.