Poet Liz Berry lived near the Wren's Nest Nature Reserve in the Black Country for years, but it was only recently that she stopped and listened to a real wren there. It made her think how the bird was hiding in the place name, which is one of Britain's most important geological sites. The wren's latin name Troglodytes troglodytes means 'cave-dweller', reminding Liz of the folk that used to work in the mines that have shaped the Wren's Nest landscape.

Produced by Sophie Anton for BBC Audio in Bristol.