Think of Bristol and the iconic Clifton Suspension Bridge and St Mary Redcliffe church may be on your list to visit. But what lies beneath? Tunnels, caves and waterways lie hidden, explored by some and missed by many. For those who know tickets on rare open days are snapped up like hot cakes. Helen Mark invites you to explore some of these gems that lie out of sight to explore the myth and history behind them.

She starts at the Redcliffe Caves whose 'rabbit warren' under the streets above reveals more about the city's ancient trades but has a modern life as a film set and theatre location. Yet the magical Goldney Grotto - lined with shells from faraway lands - could conjure images of fairytales but has its closest connection to Robinson Crusoe. While Clifton Rocks Railway - which had to remain hidden within the gorge cliffs - failed as a business, it had two new lives helping to save the lives of others.

No wonder there's so much curiosity about these hidden places!

Presented by Helen Mark