But how many of them have you heard about?
Editor's message: Thank you for reading this story. The dramatic events of 2020 are having a major impact on our advertisers and thus our revenues. The Star is more reliant than ever on you taking out a digital subscription to support our journalism. You can subscribe here www.thestar.co.uk/subscriptions for unlimited access to Sheffield news and information online. Every subscription helps us continue providing trusted, local journalism and campaign on your behalf for our city.
1. The Hole in the Road
The Hole in the Road was filled in during 1994 to accommodate the Castle Square Supertram stop. Photo: JPI Media
2. The Bear Pit
Located in Sheffield's Botanical Gardens, the Bear Pit is described as the country's finest surviving example and dates from the 1830s. It is rumoured that a child died in 1870 after falling in and being savaged. Photo: JPI Media
4. Megatron
A brick-vaulted "cathedral" often called the Megatron and located beneath Midland Station, it forms part of a labyrinth of underground rivers beneath the city. Photo: JPI Media