Embark Beach is a port run by the Zaishen Order from which every mission outpost in the game is accessible as long as it is accessible to them. The outpost is intended to make the process of finding other players to party with easier. Throughout the port are three markets, one for each continent, with well known NPC's and travel agents that can take groups to any quest or mission location in that continent.
This previously was speculated to be location of the Xunlai Market, which has been canceled. http://wiki.guildwars.com/wiki/Xunlai_Market