The western end of the Antonine Wall was built by the Romans across what is now known as the Central Belt of modern-day Scotland. The wall was 63 kilometres (39 miles), was about 3 metres (10 feet) high and 5 metres (16 feet) wide. Construction began in AD 142 and took 12 years to complete.
The western end of the wall was marked by a fort in Old Kilpatrick which overlooked the River Clyde. Nothing remains of the fort today as modern buildings and roads have been built over the site.
Links: www.antoninewall.org, en.wikipedia.org