What is Urban Exploration?
Loosely defined, it is the exploration of anything built by humans. The trick is to find places that actually count as “explorable.” To me, this means that it is largely unknown by the general population. Bonus points if they’re walking directly above such a place. Typically, UrbEx (as it is commonly abbreviated) breaks down into exploration of underground passages (e.g., drains, steam/utility/access tunnels, etc.) or abandoned buildings or other areas. This site tends to emphasize the former, but you can find more in the other categories by browsing other UrbEx sites. Find some here.