Here is a picture gallery of the most popular answers.
9. Supertram
By far the easiest way of getting around the city is on the Sheffield Supertram. Photo: Chris Etchells
10. Sheffield Hatters
Basketball fans will miss watching the Sheffield Hatters. Image: Steve Ellis Photo: Steve Ellis
11. Parks and open spaces
Sheffield is home to lots of nice parks and open spaces, such as Hillsborough Park, pictured, and Graves Park. Photo: Brian Eyre
12. John Lews
People said they would miss the city's John Lewis store at Barker's Pool. Image: Chris Lawton Photo: Chris Lawton