You will have to find a way to anchor it.
This reminds me of that time my last adventuring party and I were trying to track the umber hulks responsible for harassing a bunch of small villages in the outskirts of the Rosetree Forest. We followed their trail into the mountains nearby and discovered a small crevasse, very much like this well, that we thought was the entrance to their lair. Should've known better, in retrospect it was way too small of an opening for the bulk of a hulk. Perfect size though for a family of dire bats, who were not very pleased to be woken up in the middle of the day by a couple people dropping in on them. My wife Sadie tore our ranger a new one after that. Halfling women may seem gentle and kind, but you do not want to get on their bad side.
Anyway...anyone have any pitons?