www.rambler-info.org.uk - Symbols on Ordnance Survey Maps

The Ordnance Survey now have an excellent set of legends for their maps. You can have a quick look at them here. (They will download as an Acrobat file, which you may wish to store)

Landranger Maps (1:50,000)

Explorer Maps (1:25.000)

For much more information, please refer to their own website