Who built the wall that goes across what is now the Central Belt of Scotland?

The Antonine Wall was a turf defensive construction, one of the best known Roman fortifications built on the territory of modern Northern England. The wall represented the northernmost border of the Empire, being more than 60 kilometers (or approximately 40 miles) long. The fortification was built at the order of Antoninus Pius, a Roman Emperor, who was famous for his passion and desire to enlarge cities and construct new buildings.

The wall had been being built in the course of 12 years and protected 16 forts. Nowadays the ruins of the wall are less evident than the better-known Hadrian's Wall to the south, primarily because the turf and wood wall has largely weathered away, unlike its stone-built southern predecessor. Anyway, it remains an important object of historical heritage of the country and is protected by UNESCO.