Mine are in a hutch/run attached on concrete. I also put them into a separate run on grass - but as others have commented, they ruin the grass - mine with digging. I will have to get a good rain cover for the run and hutch soon, though, as the bottom of the hutch is more exposed - taken door off so run could be attached. It's a two storey hutch so they they have a dry, boarded bedroom area, as well as space to use as a living area, upstairs. I find it easier having the run attached. We're in and out a lot - we don't have to tear back from where ever we are if there's a sudden downpour because we know they'll hop into the hutch to keep dry. You have to do what suits you best and work out a routine that keeps you and your buns happy, imo. :wave: