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Who was Emperor Hadrian? -

Hadrian was Roman emperor from 117 to 138 CE. He's regarded as having unified and consolidated Rome's vast empire.

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Touring the Roman Empire -

In 121, Hadrian embarked on a tour of the Empire, west to east. His aim was to inspect troops and examine frontier defensives.

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Arrival in Britain -

Hadrian arrived in Britain in 122. After visiting the country's lawless north, the emperor expressed concern over tribal revolts in the region.

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Northern barbarians -

There was unrest and rebellion in Roman Britain, and Rome's grip on the territory was being threatened by barbarian tribes, including the Picts.

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Maintaining the Empire's integrity -

It was Hadrian's wish to keep the Empire intact, which he believed had been imposed on him through divine instruction.

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Limes Germanicus -

He hit upon the idea of building a wall to separate the Romans from the barbarians. Rome had already built a similar line of frontier fortifications in the provinces of Germania to divide the Empire and the unsubdued Germanic tribes. These defenses were known as the Limes Germanicus.

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Construction begins -

Construction of Hadrian's Wall began in 122. It's purpose was to separate the province of Britannia from contested land to the north.

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The wall's dimensions -

The wall was to be 80 miles (128 km) long, 20 feet (six meters) high, and 10 feet (three meters) wide, and built of stone.

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A defensive line -

The wall's defenses were to be reinforced by turrets, ditches, milecastles, and 16 forts each capable of holding 500 to 1,000 troops.

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Recruiting troops -

These soldiers were to be drawn from all four corners of the Empire, including Spain, Switzerland, Germania, and North Africa. Some would also be recruited locally.

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Completion of the wall -

The initial construction of the wall took approximately six years. Expansions were made later, but by 126 it was largely completed.

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A physical barrier -

As a physical barrier, the wall slowed the crossing of raiders, people intent on infiltrating its defensives smuggling animals, treasure, or slaves, and then returning with their loot.

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A psychological barrier -

The design of the wall also served symbolic and psychological purposes. It was a tangible statement of Rome's imperial power, and acted as a psychological barrier between the "civilized" Roman territories and the unconquered barbarian wilderness.

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The Picts attack -

However, the mighty structure failed to deter the Romans' fiercest foes, the Picts.

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Tattooed warriors -

Picts were inhabitants of Caledonia (modern-day Scotland) and were so named because of their use of culturally significant body tattoos. Picti means "painted one" in Latin.

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Harassing the enemy -

The Picts, with both male and female warriors, harassed the Romans with frequent raids.

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The wall is extended -

To counter their persistent enemy, the Romans began extending the wall, building a fort in the year 128 at Arbeia as a supply base.

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Hadrian's successor: Antoninus Pius -

In 138, Hadrian died, his wall still under siege by Picts who simply attacked the area around it. Hadrian's successor, Antoninus Pius, ordered the construction of a new defensive wall—the Antonine Wall—built further north in an attempt to quell a major uprising by the Brigantes.

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The wall is breached -

Successive assaults on both Hadrian's Wall and the Antonine Wall tested Roman strength and resolve. In the 180s, the Picts even breached Hadrian's wall, albeit briefly.

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Roman collapse -

Over the next two centuries, both walls held. In the late 4th century, though, barbarian invasions, economic decline, and military coups loosened the Empire's hold on Britain. Roman rule finally ended in Britain in 383 CE. 

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Hadrian's Wall today -

Hadrian's Wall still exists, despite almost all the standing masonry of the structure having been removed in early modern times and used for local roads and farmhouses.  

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Archaeological excavation -

None of its stands at its original height, though archaeological excavation over the years has exposed much of the top levels

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Arbeia Fort -

Excavations have also unearthed some remarkable finds, including the well preserved ruins of Arbeia Roman fortress, the supply base built in 128.

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Housesteads Fort -

Another exceptional archaeological site is Housesteads, a military outpost that served as an auxiliary fort for Roman troops. Housteads is the best preserved Roman fort in the United Kingdom.

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Hadrian's Wall Path -

Most of the wall can be admired by following the Hadrian's Wall Path. It runs for 84 miles (135 km), from Wallsend on the east coast of England to Bowness-on-Solway on the west coast.

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Milecastle 39 -

A section of the path passes the foundations of Milecastle 39. Milecastles were small garrisons housing up to 30 Roman troops. As the name suggests, these garrisons were positioned at every mile (1.5 km) along the wall.

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High and wild -

Walking the path is a relatively easy hike. The section between Chollerford and Walton is the highest and most rugged part of the path, at 1,330 feet (345b m).

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Vindolanda Fort -

Lying south of Hadrian's Wall and a worthwhile diversion is Vindolanda. Another auxiliary fort, Vindolanda in fact predates the wall, having been constructed in 85 CE.

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UNESCO World Heritage Site -

Hadrian's Wall was designated a UNESCO World Heritage Site in 1987.

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UNESCO protected -

Then lesser known but equally compelling Antonine Wall was granted the same honor in 2008. 

Sources: (England's North East) (Britannica) (Smithsonian Magazine)

See also: World Heritage Sites that could disappear anytime

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