The MUD was founded in 1991 and opened to the public in 1992 (receiving continuous updates since then, now thirty years later). Originally containing a small section of the then rather loosely defined Ankh-Morpork, over time more locations have been added as the world has been further described in the book series, and laid out in the map supplements (such as The Streets of Ankh-Morpork and The Discworld Mapp). It now consists of areas that attempt to simulate several big cities (Ankh-Morpork, Bes Pelargic, Genua and Djelibeybi) on two continents, a larger number of smaller towns, and more than a million rooms which form the land between the cities and towns, with markers designating canon cities yet to be built.