Before revision: Overview HistoryThe Ordnance Survey began producing six inch to the mile (1:10,560) maps of Great Britain in the 1840s, modelled on its first large-scale maps of Ireland from the mid-1830s.
After revision: HistoryThe Ordnance Survey began producing six inch to the mile (1:10,560) maps of Great Britain in the 1840s, modelled on its first large-scale maps of Ireland from the mid-1830s.