History of the British Ordnance Survey Maps
The Ordnance Survey 1-inch First Edition Map Sheets ("Old Series" Maps)
The Ordnance Survey 1-inch First Edition map sheets were based on the one-inch-to-the-mile scale (1:63,360) and followed a standard sheet size.
The "Old series" map was first published in 1805, covering England and Wales in its entirety by 1869 (though a 'New Series' had already been authorised and began in 1863). Regarding the one-inch-to-the-mile maps on our ARCHI MAPS: UK website, it used a variation on the Cassini Projection using Delamere as its origin - this may cause distortion in some areas as we have attempted to reproject the map onto the more modern Web Mercator projection to work on modern web viewers. Please note due to this it is only possible to give an approximate modern geographic reference of areas on this map, with geolocation most accurate near the coasts and least accurate towards the centre of the country.
Sheet Dimensions / Size (Standard)
- Width: 24 miles (38.6 km)
- Height: 18 miles (28.9 km)
- Area Covered: 432 square miles (1,118 km square)
- Scale: 1:63,360 (1 inch = 1 mile)
These dimensions were based on the standard Ordnance Survey 1-inch maps covering an area of 432 square miles (1,118 km squared) per sheet.
Ordnance Survey 1-Inch First Edition Map Coverage & Evolution
The Ordnance Survey (OS) 1-Inch First Edition maps were the first comprehensive topographical maps of the UK, covering England, Scotland, and Wales. They were surveyed primarily in the early 19th century, with some variations in coverage over time. 1-Inch First Edition Map Sheet Details
Survey Period
- England & Wales: 1805–1870s
- Scotland: 1843–1878
Sheet Dimensions / Size (Standard)
Publication Period
- Initial editions: Early 19th century
- Regular updates followed in later decades
Coverage & Divisions
Each sheet covered an area of roughly 24 x 18 miles, ensuring a manageable balance between detail and coverage.
The layout of sheets was not always perfectly aligned with county boundaries, as they were designed for consistent mapping rather than administrative divisions.
Ireland was mapped separately by the Ordnance Survey of Ireland, using a similar scale but different sheet arrangements.
Later Developments & Successors
Revised New Series (1880s–1900s)
Improved accuracy and included more up-to-date details.
Some sheets were extended or altered slightly to fit administrative changes.
Popular Edition (1919–1926)
More modern, colorful, and revised versions, aimed at public use.
Fifth Edition (1930s)
Incorporated further refinements in style and road classifications.
Seventh Series (1952–1961)
The last complete 1-inch series before OS moved to the 1:50,000 scale.
Variations in Scotland & Ireland
Scotland often had a different grid layout due to its more rugged geography.
Ireland’s OS mapping was carried out separately, using different numbering but following a similar format.