Great London Buildings: The Roman Wall

The London Wall, originally built around Londinium by the Romans around 200 AD, represents one of the most significant ancient structures in Britain’s capital. The wall defined London’s boundaries for over a millennium, and portions of it remain visible today across the City of London.

The original construction took place between 190-225 AD, during the reign of Emperor Septimius Severus. The wall stretched for approximately 3.2 kilometers (2 miles), enclosing an area of about 330 acres. Built primarily of Kentish ragstone brought from quarries near Maidstone, the wall stood approximately 6 meters (20 feet) high and 2.5 meters (8 feet) thick, with a defensive ditch (or vallum) in front.

The wall’s architectural design included a series of gates at key points: Aldgate, Bishopsgate, Newgate, and Ludgate, with Aldersgate added later. These gates were more than simple openings; they were substantial structures that controlled access to the city and collected tolls. The wall was also fortified with defensive towers placed at regular intervals, approximately every 50 meters.

Today, visitors can see several well-preserved sections of the Roman wall across London. Here are the key locations:

• Tower Hill: One of the most impressive surviving sections stands near Tower Hill tube station. This segment includes Roman masonry at its base, with medieval additions above. The site includes informative plaques explaining the wall’s construction and history.
• Cooper’s Row: Behind the Grange City Hotel, visitors can see one of the best-preserved sections, incorporating a Roman tower base. This section stands almost to its original height and clearly shows the distinctive red tile layers used by Roman builders.
• London Wall: Along the street named London Wall, particularly near the Museum of London, several sections remain visible. The most notable is the stretch within the Barbican complex, where a substantial portion of the wall stands alongside a medieval church tower.
• Noble Street: Near the Barbican, this section provides an excellent example of the wall’s construction techniques, with clearly visible bonding tiles and ragstone layers. The site includes detailed information panels about the wall’s history.
• St. Alphage Garden: This public garden contains a well-preserved section of the wall that later formed part of the medieval church of St. Alphage. The different building phases are clearly visible in the stonework.

The wall underwent significant modifications throughout its history. In the medieval period, it was heightened and strengthened, with additional gates added. The Romans’ original construction technique can still be identified by the characteristic red tile bonding courses used to strengthen the ragstone walls.

The engineering of the wall was remarkably sophisticated. The foundations were typically 2.4-3 meters deep and built of chalk and gravel, topped with thick pieces of sandstone. The main structure used the distinctive Roman technique of laying courses of squared ragstone with red tile bonding courses every few feet.

During the medieval period, the wall played a crucial defensive role and helped shape London’s development. The gates became important landmarks, giving their names to areas of the city that are still used today. The wall’s course influenced street layouts that remain visible in modern London’s street pattern.

Archaeological investigations have revealed much about the wall’s construction and history. Recent discoveries include evidence of repairs and modifications from various periods, as well as the identification of additional Roman bastions and towers not previously documented.

The wall’s influence on London’s development cannot be overstated. It defined the city’s limits for centuries and influenced its street pattern and property boundaries. Many modern streets still follow its course, including London Wall, which runs along part of its northern section.

Conservation efforts have preserved many sections of the wall, with several having been incorporated into modern buildings. The Museum of London has played a crucial role in interpreting these remains, providing context through exhibitions and educational programs.

Today, the London Wall represents one of the city’s most important archaeological treasures. Its remains provide tangible evidence of Roman engineering and construction techniques, while its influence on London’s development continues to be visible in the modern city’s layout and structure.

A walking trail known as the “London Wall Walk” connects many of the surviving sections, marked by plaques installed by the Museum of London. This trail allows visitors to trace the wall’s course and understand its historical significance in shaping the city of London.

The preservation of these Roman wall sections amid modern development demonstrates London’s commitment to maintaining its historical heritage while accommodating growth and change. Each surviving section tells part of the story of London’s evolution from Roman Londinium to the global city it is today.

Author: Jonathan Thomas

Jonathan is a consummate Anglophile who launched Anglotopia.net in 2007 to channel his passion for Britain. Londontopia is its sister publication dedicated to everything London.