An easy place to get this achievement is the templecave of Toxai. There is plenty of other places where to get this achievement but this is the safest and the fastest i found so far.
Spawn at Morin Kur, exit the city taking the direction of the gravenyard (you can find signs inside the city) and reach Toxai. In the docks of Toxai, close to a big ship in the sea, there is a really big cave in a rock recess, you will not see it if you are not close to it.
Inside the cave, follow the spiral pathway up until you see a chest, thats the jump zone. You will probably survive with 2-3hp and get the achievement.