Guildford / ˈ ɡ ɪ l f ər d / ( listen) is a large town in Surrey, England, United Kingdom located 27 miles (43 km) southwest of London on the A3 trunk road midway between the capital and Portsmouth.. The town has a population of about 80,000 and is the seat of the wider Borough of Guildford which had an estimated 146,100 inhabitants in 2015. Guildford has Saxon roots and historians ...