Astley and Bedford Mosses are areas of peat bog south of the Bridgewater Canal and north of the Liverpool and Manchester Railway.

They are situated about 2+1⁄2 miles (4 km) south-east of Leigh, in Astley and Bedford, Greater Manchester, England.

They are among the last remaining fragments of Chat Moss, the raised bog that once covered a large area, of around 10+2⁄3 square miles (28 km2), south Lancashire north of the River Mersey.

[3] Chat Moss, a lowland raised bog, formed after the last ice age about 10,000 years ago on the site of a shallow glacial lake to the north of the River Mersey.

Sphagnum mosses increase the acidity of the water resulting in highly specialised plant species, many of them found nowhere else.