If you look under the general category of achievements, then under “explorer”, there is an HoT exploration achievement titled “Dragon’s Stand”. There are two areas listed for this achievement that aren’t on the map. Thorn Hollow and Deserted Coast. They are in the Wiki.
https://wiki.guildwars2.com/wiki/Dragon's_Stand
One poster claims that by cheating and going outside the map you can get Deserted Coast
https://www.reddit.com/r/Guildwars2/comments/3r6z9p/need_help_with_some_dragons_stand_achievement/