Time Zones

[Lukourgos]

Why do the Canary Islands keep to the same times as the U.K. throughout the year rather than those of Spain?

[mushroom25]

because of their geographical location at approx 15deg west, actually further west than the British Isles.

[Buenchico]

Mushroom25's got it spot on.

Time zones are defined by location rather than nationality. The basic principle with assigning times to a specific place is that it's 12.00 noon when the sun is at it's highest point in the sky. (This ignores 'Summer Time' or 'Daylight Saving Time' which are recent man-made 'tweaks' to the system).

Early 'time zones' used to be a very local thing. Up until the 19th century, times in Bristol were not the same as in London. (This was because the sun is at its highest point in the sky slightly earlier in London than it is in Bristol. So London clocks used to be several minutes ahead of those in Bristol). It was only the coming of the railways which resulted in 'London time' being used throughout the UK.

World-wide time zones are likewise based upon the principle that it's 12.00 noon when the sun is at its highest point in the sky. Rather than having country A's time 38 minutes ahead of Country B and country X's time 7 hours and 18.5 minutes behind country Y, all times are rounded to the nearest hour to make things simpler. (To be really accurate, that should read 'most times' because there are a small number of places where one time zone is only 30 minutes different from a neighborouring zone but this is fairly rare).

Chris