Martin wrote:
They can climb blank walls. We had mice climb a larder wall that had a
supermarket plastic bag full of packets of crisps hanging on a hook on
wall. They not only got into and out of the bag, they also ate a lot
of the crisps.

They keep nibbling the underside of things in our fruit bowl. :-(
It's extremely unpleasant to pick up an item of fruit and find your fingers
go into the squishy nibbled invisible bit.