Tromping around old mines and ghost towns can be a real fun time experience. There is a lot of old history to be seen and one can usally find old relics from the past laying around if the area hasn't been pick to clean by others.
However, if you plan on going out to visit some of these old sites you really need to be prepared. Most of the old mines are well off the beaten track and the roads or trails to get there are in most cases are not well travelled. Make sure you have have lots of "EXTRAS".
Extra spare tire
Extra batteries for GPS, flashlight, headlamps etc.
I pack an Extra fan belt always
First aid supplies
some simple mechanical tools/knife/maybe a firearm
GPS and an old fashion compass
Snake bite kit/bear spray
20 feet of good rope minimum.
Anything else you can think of
Never go alone. Always take someone else with you. Be sure to tell others where you are going and when you think you will be back. Be sure to check in with you contacts if possible just prior to heading into the back country. If your going through park area be sure to let park staff know also.
Once your at your destination be watchful of the ground around you. In reality, these places are just old dump sites. There can be a lot of old junk laying around from bent rusting steel to busted glass. There's lot of things that can cut or stab that are hidden in the grass or bushes. Depending on your location there can be snakes or in some areas, bears. Most of these places were mining towns and people dug everywhere. There can be old hand dug wells or shafts anywhere. Some can be covered over with a few old boards or maybe some in grown brush, but step in the wrong spot and down you go. You can go down anywhere from a few feet to hundreds of feet down. Remember the old timers 100 years ago or so just up and left and they weren't thinking about your well being.
Use extreme caution touring old buildings. Rotten flooring. Roofs that are cave in ready. Walls ready to fall. Rusty nails sticking out everywhere.
Wanting to venture into an old mine is always tempting. Inside old mines is very dangerous. It is best NOT to go into old mine portals. Old mines can be deadly so best advised to stay out. Caveins, gases, rottening timbers are all a recipe for disaster and death. Many people have died playing around in old mines Best way to visit the old mines themselves is to read about them on websites like this. It's much better for your to read about them that have others reading about you. In your obituary.