Discounting Antarctica and its ice sheets, only one other continent (Asia) borders three oceans, but the inward-draining endorheic basin area of Central Asia from western China to the Aral and Caspian Seas is so vast that any Arctic and Indian Ocean tributaries are never within proximity of each other. Thus, North America's status of having a single location draining into three oceans is unique in the world. (Some sources, however, consider Hudson Bay to be part of the Atlantic and, thus, Snow Dome - partially in Jasper National Park, on the border of the provinces of Alberta and British Columbia, Canada - to be the continent's sole hydrological apex.)