British Summer Time
British Summer Time (BST) starts on the last Sunday in March and ends on the last Sunday in October, at 1.00 am Greenwich Mean Time (GMT):

in spring the clocks go forward, losing an hour - at 1.00 am GMT the UK moves to 2.00 am BST
in autumn the clocks go back, giving an extra hour - at 2.00 am BST the UK moves to 1.00 am GMT
In the next three years, the summer time periods begin and end on the following dates:

                   2009      2010       2011
Clocks go forward 29 March   28 March   27 March
Clocks go back    25 October 31 October 30 October


Double British Summer Time ended in 1945.

http://en.wikipedia.org/wiki/British_Summer_Time