Mysterious Roman dodecahedron to go on display in Lincoln

There are no known descriptions or drawings of object in Roman literature, making its purpose unclear

They are known as one of archaeology's great enigmas - hollow 12-sided objects from the Roman era with no known purpose or use.

Only 33 of these mysterious dodecahedrons have ever been found in Britain and now one, unearthed during an amateur archaeology dig after 1,700 years underground, is going on public display in Lincoln as part of a history festival.