Ilshenar is a much more wild land than Britannia, being mainly composed of mountains, forest and swamps. Mislas and Monlor are the two main cities of Ilshenar, otherwise only little civilisation has touched the lands. Ilshenar is made up of many dungeons and is home to new monsters. Originally, it was only accessible to those using the updated client that came with the expansion. Later, in the next expansion, Ultima Online: Lord Blackthorn's Revenge (February 24, 2002) Ilshenar was opened to those using the original client.