Glevum (or, more formally, Colonia Nervia Glevensium, or occasionally Glouvia) was a Roman fort in Roman Britain that became a "colonia" of retired legionaries in AD 97. Today, it is known as Gloucester, located in the English county of Gloucestershire. The name Glevum is taken by many present-day businesses in the area and also by the 26-mile Glevum Way, a long-distance footpath or recreational walk encircling modern Gloucester. 
Glevum was established around AD 48, at an important crossing of the River Severn, and near to the Fosse Way, the early front line after the Roman invasion of Britain. Initially, a Roman fort was established at present-day Kingsholm. Twenty years later, a larger replacement fortress was built on slightly higher ground nearby, centred on present-day Gloucester Cross, and a civilian settlement grew around it. The Roman Legion based here was the Legio II Augusta, as they prepared to invade Roman Wales between 66 and 74 AD.
In AD 97, the whole area was designated a colonia by the Emperor Nerva. A colonia was the residence of retired legionaries and enjoyed the highest status in the Empire. The legionaries were given farmland in the surrounding district, and could be called upon as a Roman auxiliary armed force.
Roman Britain was divided into four provinces in the early 4th century. It is most likely that Glevum, as a colony, became the provincial capital of Britannia Secunda, in the same way that colonies at York and Lincoln became capitals of their respective provinces. There is some evidence that at this time Glevum possessed a mint.
At its height, Glevum may have had a population of as many as 10,000 people. The entire area around Glevum was intensely Romanised in the second and third centuries, with a higher than normal distribution of villas, as a result of its suitability for the traditional intensive Roman farming methods.
Excavations at Gloucester's New Market Hall in the 1960s showed that Romano-British occupation of the town may have continued in some form into the sub-Roman period, even if the town's population may have been greatly reduced. A new portal in the town's wall was built at the beginning of the sixth century, showing a modest growth of the town after the Battle of Mons Badonicus in 497.
The Anglo-Saxon Chronicle records a King Coinmail (according to the original A-text), who may have come from Gloucester, taking part in the Battle of Dyrham in 577, when the city was conquered by the Anglo-Saxons.
- Many archaeological artifacts and some in situ walls from Roman Glevum may be seen in the Gloucester City Museum & Art Gallery
- The remains of the Roman and medieval East Gate are on display in the East Gate Chamber on Eastgate Street.
- There was a small display in the former Royal Bank of Scotland premises on the Roman finds found from the site, but the branch has now closed and the building is currently empty.
- Northgate, Southgate, Eastgate and Westgate Streets all follow the line of their original Roman counterparts, although Westgate Street has moved slightly north and Southgate Street now extends through the site of the Roman basilica.
- An equestrian statue of the Emperor Nerva was erected at the entrance to Southgate Street in 2002. It was created by Anthony Stone and paid for by public subscription, following a campaign that started in 1997, the 1900th anniversary of the colonia's foundation.
- Glevum Way Summary - the Long Distance Walkers Association
- "Archived copy". Archived from the original on 2011-09-27. Retrieved 2013-06-09.CS1 maint: Archived copy as title (link) The colonia of Glevum
- Hassall, M; Rhodes, J (1974). "Excavations at the new Market Hall, Gloucester 1966-7". Trans Bristol Gloucestershire Archaeol Soc. 93: 15–100.
- Wallace, Collin. "Makers' Stamps on Mortaria from Gloucester" (PDF). Study Group for Roman Pottery. Retrieved 25 February 2019.
- "The Nerva Statue". gloucester.gov.uk. 9 September 2010. Archived from the original on 29 November 2014. Retrieved 18 November 2014.