Best hostels you’ve volunteered at in Europe?

Hey!

I’m planning a longer trip around Europe and looking to do a few hostel volunteer stays along the way. I have no specific countries in mind yet, anywhere in Europe really. Then i will contact the hostels and see if they have anything avaliable.

Curious what are the best hostels you’ve volunteered at?
Why were they the best?

Would be great to hear some personal experiences (good or bad).

Thanks!