|Peerless - Newberry Springs, California|
Often (but not always) trespassing is required to gain access into abandoned buildings. There is a risk of getting caught, although most times the property owners don't really know or care that there are trespassers--these are often "forgotten" places. Also, urban explorers are not intending harm to the structures or property. A common motto is "Take only pictures, leave only footprints."
There are many reasons why people are urban explorers. There is a fascination with what has been abandoned. There are often historical significance to the buildings. There is a thrill with elements of danger.
And there are certainly elements of danger. Besides getting caught and potentially arrested, almost always these structures are in a state of dilapidation. There's often broken glass and rusty nails. Mold and asbestos could be present. There might be all kinds of dangerous creatures. This is not a safe activity.
It is, however, an interesting activity--one that has captivated me. I very much enjoy urban exploration, and I especially enjoy creating photographs of abandoned places.