The first four expansions were released in traditional physical boxes at roughly one-year intervals. These were highly ambitious and offered huge new landmasses, new playable races and new classes. The expansion ' (2001) gave a significant facelift to player character models, bringing the dated 1999 graphics up to modern standards. However, non-player characters which do not correspond to any playable race-gender-class combination (such as vendors) were not updated, leading to the coexistence of 1999-era and 2001-era graphics in many locations. The expansion ' (2002) introduced The Plane of Knowledge, a hub zone from which players could quickly teleport to many other destinations. This made the pre-existing roads and ships largely redundant, and long-distance overland travel is now virtually unheard of.