Avon was a county in southwestern England. It existed from 1974 to 1996. The county included the historic port city of Bristol and what had been the southern part of Gloucestershire and the northern part of Somerset. The city of Bath stands in the region. Bath's terrace (row) architecture and Roman baths have made it a famous tourist center. The River Avon flows through the middle of the region. It has cut a spectacular passage at Clifton Gorge. Spanning the gorge is the Clifton Suspension Bridge, designed by English engineer Isambard Kingdom Brunel and completed in 1864.