Posted by Quadrifoglio I noticed in a "what to bring with you" thread that many people suggest bringing Duct Tape along. While it won't last forever perhaps writing "No Step" in duct tape on a door that opens to a drop off would be sensible? Of course each site and danger is unique so there is no one size fits all.

I suppose you could put duct tape on the wall and write on the tape with a sharpie. Permanent, but removable.

Posted by DescentOnARope This is what worried me most: https://farm9.staticflickr.com/8677/16434792052_41c91fa675_o.jpgdeathtrap by dizzle229, on Flickr It may not look like much, but there's a large piece of plywood directly in front of it. Anyone not paying attention might easily round the corner and have a bad time, in a place where just such a person might come through.

I came across a very similar hole directly through a door like that as well not too long ago... discovered it after who I was with stepped right over it without even noticing and after realizing what it was and the fact it dropped ~3 stories I've been MUCH more aware as I'm walking around now.

I slid a chair over it to span the gap and make someone have to move it before passing it, this is what I'd like to see more instead of painting - using stuff in the immediate area if possible to show where hazards may be.

^This!
And the duct tape with sharpie is a good idea.
You can also use chalk..? I rock climb a lot, and we keep thick pieces of chalk with us to mark rocks that are loose and ready to fall, so that you don't try to climb up them and toss them on the people below you. Some people use spray paint for that, but it's still considered vandalism, no matter how good your intentions are.

In the abandoned mines that we explore we often see "warnings" and exit markers painted throughout the mine. Unfortunately there are so many idiots that walk in cans of paint and "help" by painting exit arrows and "danger" markings everywhere they go. In the end there are warnings and arrows that point every different direction. Some times side by side pointing opposite direction. Of course vandals simply wanting to find meaning in their lives by painting their name EVERYWHERE are frequent mine visitors.

As a beginning explorer I found the messages more confusing than helpful, often simply wrong. As an experienced explorer I lament that these historical locations are strewn with markings that were painted long after the mine was abandoned. We occasionally find our way into a difficult to access location in a mine where it has not been visited for a very lone period, possibly the original miners. Although natural decay has set in, the sense of walking into history is overwhelming for me.

My vote is to leave locations intact. No warnings. No markings. No names.

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