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

我们发现一些相当有趣洞穴，但我们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".

它样也被称为“下水道探索”，“城市洞穴探险”，“建筑探险”等等。