Yate and Chipping Sodbury sit right at the base of the south western escarpment of the Cotswold Hills while Old Sodbury itself sits right on the escarpment itself overlooking the Frome, Avon and Severn valley. Cotswolds comprise of the Cotswold Hills, a range of rolling hills that rise from the meadows of the upper Thames to an escarpment, known as the Cotswold Edge, above the Severn Valley and Evesham Vale. The area is defined by the bedrock of Jurassic limestone that creates a type of grassland habitat rare in the UK and that is quarried for the golden-coloured Cotswold stone. It contains unique features derived from the use of this stone; the predominantly rural landscape contains stone-built villages, historical towns and stately homes and gardens. Designated as an Area of Outstanding Natural Beauty (AONB) in 1966 the Cotswolds covers 787 square miles (2,040 km2) and, after the Lake District and Yorkshire Dales national parks, is the third largest protected landscape in England and the largest AONB.