Explore Highmountain

If you want to cheese it, simply use Warband Map to Everywhere All At Once (you can find it in Spellbook -> General -> Warbands) - it will instantly complete all the "explore" achievements, if you previously fully discovered these areas on any of your characters.

Waypoints for all areas. Explore Highmountain is needed for [achievement=42642]

/way #650 43.0 33.5 Bloodhunt Highlands
/way #650 29.3 33.4 Blind Marshlands
/way #650 49.8 79.6 Frosthoof Watch
/way #650 47.9 68.9 Ironhorn Enclave (path start)
/way #650 55.6 83.9 Ironhorn Enclave
/way #650 27.3 54.6 Nightwatcher's Perch
/way #650 43.1 51.7 Pinerock Basin
/way #650 38.9 67.8 Riverbend
/way #650 56.4 21.8 Rockaway Shallows
/way #650 43.7 8.7 Shipwreck Cove
/way #650 52.6 44.8 Skyhorn
/way #650 58.7 64.7 Stonehoof Watch
/way #650 35.6 63.6 Sylvan Falls
/way #650 46.2 61.4 Thunder Totem
/way #650 35.2 45.7 Trueshot Lodge