Unusual but true: 25-year-old burger looks brand new

In unusual but true stories this week, we have a 25-year-old McDonald's burger; planet Mercury passing across the face of the Sun; a barge that had been stuck for over a century breaks free; and a "house" floating down the River Thames.

All the odd and interesting anecdotes from around the world are here in our review.

25-year-old McDonald's burger

A McDonald's burger allegedly bought in 1995 and kept in an Australian shed for years has never decomposed. Though the burger has shrunk a little from its original size, its shape remains intact, there are no signs of mould, and it doesn't smell.

Casey Dean, 39, and Eduards Nits, 38, claim they ordered the Quarter Pounder with cheese from a McDonald's outlet in Adelaide as teenagers - and have hung onto it ever since. Their claims have made headlines days after a live stream of a decade-old McDonald's cheeseburger displayed in a glass case in Iceland went viral.

Now the burger is on display like a work of art inside a glass case at a hostel in southern Iceland. Dean, owner of the Australian rival for the oldest McDonald's, said the packaging – waxy paper and a cardboard ring – accurately date the burger to the mid-1990s.

Dean said: "It started a chain of events where we were joking 'imagine if we kept this forever', and here we are."