Vehtendi Valley is an Explorable area in Vabbi. Like the Yatendi Canyons to the south of it, it is along the banks of the Elon, and the narrow lenges along the east bank on the Elon are indeed remeniscant of that region, but the rest is much more open, with farmlands in the Southwest, and the outskirts of Yahnur Market in the Northwest. The beautiful Hanging Gardens of Jahin may be seen (but not entered) in the Northeast.
Having the quest The Hanging Gardener will give you a level 20 ranger ally and he can be used to help vanquish if needed.
The accessible paths in this area form a closed loop, with Yahnur Market "breaking" the loop because there is no path around it. Because of this, it is recommended to begin vanquishing the area from Yahnur (either exit) and progress around the area until you reach the other Yahnur exit.