洞穴探险

We found some really interesting caves, but we didn't have the gear to go spelunking.

我一些相当有趣的洞穴，但我没有装备去进行洞穴探险。

It may also be referred to as "draining" (when exploring drains) "urban spelunking", "urban caving", or "building hacking".

它同样也被称为“下水道探”，“城市洞穴探险”，“建筑探险”等等。