There's a local quarry that is no longer in use (for many decades), and has 30-40ft walls. Much of the material on the wall is very crumbly, especially near the blast holes: blast hole

There's still a large amount of fairly hard rock, including quartz and gneiss, though the crag does get very wet when it rains.

Given how labor and time intensive crag development is, not to mention safety and access issues, what's the general sentiment about the safety of old quarries? Is it possible to break off the rotten rock to expose stronger rock underneath? Or is it not worth the effort?

Also side note, we need a geology and crag-development tag!

  • An example would be the Riverside Quarry in Southern California: mountainproject.com/area/105902982/… My personal experience with the place was bad, because I got seriously injured due to loose rock.
    – user2169
    Feb 16, 2021 at 0:07
  • 1
    "Is it possible" questions usually lack focus, unless you specify what resources you are able and willing to commit to the task at hand. Feb 16, 2021 at 19:40
  • 1
    There are some crags in former quarrys, so it is not impossible. However, whether it is worth putting in time and effort really depends on the specific situation. It would probably be best to build an anchor at the top and top rope a bit. You will see how crumbly it actually is and how much it affects climbing if holds break off
    – Manziel
    Feb 17, 2021 at 10:56
  • @Manziel: Toproping in an area with bad rock quality is not necessarily safe. The belayer can be hit by rock fall. Rappelling to inspect the rock is probably safer.
    – user2169
    Feb 19, 2021 at 16:45
  • We certainly will not be top roping this area until significant exploratory effort on rappel has been made and we are sure the loose rock has been cleared Feb 19, 2021 at 20:34

1 Answer 1


You might as well ask "How long is a piece of string?" - everything depends on the local geology.

There are thousands of quarries that have been developed for cragging. But there must be a great many more that will never be suitable.

Initial research

The rock in your picture doesn't look very promising, to be frank, so you might want to do some initial research before committing to the project.

You should discover whether the rock being quarried for building stone or for aggregate. If it was an aggregate quarry you are almost certainly wasting your time.

Is there any similar rock in the vicinity that is climbable and gives you cause for optimism?

If you can find a local geologist, they might be able to advise on the suitability of the rock type.

Arranging legal access

If things still look promising the next step, obviously, is to get permission from the land-owner. Depending on your local laws, this might not be straightforward if there are any issues with liability. Many climbing clubs have access officers who might be able to help.

Suck it and see

If you do get permission you will realistically just have to suck it and see. But the dangers of loose rock are very real so take every precaution. Don't be going there after frost or heavy rain. Do abseil inspections if there are safe belays at the top (and if there are no safe belays, is this really an area where you want to be climbing?). Even after initial cleaning you might want to top-rope the first few routes until you gain full confidence in the rock.

Putting up new routes is fun, but please do be prudent and don't take excessive risks. It's possible that you've stumbled on a hidden gem. But it's much more likely that there are good reasons why this quarry has never been developed!

  • The picture is just from google,I didn't have any pics available at the time! But the good thing (bad thing?) Is that the land is already on a conservation easement, so we could be looking at invasive plant cleanup in exchange for land access with the owner... Pending rock quality of course! If you have any books or resources on development I'd love to read up! My initial searches on this topic yielded nothing, so the broadness of the question is in some ways related to the relative dearth of info out there. Feb 22, 2021 at 16:12
  • I have involved the local access org, so we'll be doing an in person inspection and I'll be posting an answer of my own with specifics of what we look for as I learn! The good thing is there are plenty of well rooted trees at the top to abseil off, so we're set there. There's also quite a few nice boulders at the base that are very solid, and some promising looking blocks with good hardness up on the wall itself; I think if we can do some significant cleanup there is good chance of quality rock underneath. Feb 22, 2021 at 16:16

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.