What causes sinkholes and why has Britain seen a spike?
Geologists are warning that the prolonged flooding and wet weather will lead to more sinkholes appearing across the UK over the coming months.
At least six are known to have opened up over the past month, including a 5ft hole that appeared under a house in Ripon on Monday night.
The BBC's Science Editor David Shukman assesses how and why the sink holes form.
18 Feb 2014
- From the section Science & Environment