Clocks go Back from BST to GMT

On Sunday 26 October 2003 clocks need to be put back one hour at 2am

Precisely, at 1am GMT (Greenwich Mean Time) time in Britain will be switched from 2:00 BST (British Summer Time) back to 1:00 GMT. So just when you get use to it getting dark around 6pm, it will be dark a whole hour earlier. The good news is that, on Sunday morning, you might be feeling that you may stay in bed an hour longer until your internal clock has adjusted to GMT (or wintertime), usually by Wednesday or Thursday.
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But why to we have to switch the clock anyway? Before the railways, most people kept time by the sun. With the coming of the railways, it became a significant problem for timetables that the time at one end of a railway line should differ significantly from that at the other. For this reason, in the 1840s the railway companies started to keep London time consistently at their stations and on their trains. This London mean time was labelled Greenwich mean time later.

The year 1916 brought us the institution of Summer Time, advancing the GMT by one hour during the summer months in order to promote greater efficiency in the use of the daylight hours and of artificial lighting. Summer time has been originally introduced as a World War I measure, but has been continued through peacetime as well, with occasional variations such as double summer time (advancing the clocks by a second hour for part of the summer) in World War 2.

While the positve and negative effects are highly debated up until today the members of the EU placed the common dates and times for Summer Time on a permanent footing. The EU specified a common start time, from 2002 onwards, of 1am Greenwich Mean Time on the last Sunday in March, and a common end time, from 2002 onwards, of 1am Greenwich Mean Time on the last Sunday in October. Thus BST will be back on Sunday 28 March 2004, when the clock goes forward 1 hour to 2am BST.