The Roman Kiln

Discovery

It’s 50AD...high up on a ridge in a wooded area 5 miles north of Londinium, a group of people are busy building kilns to fire some simple pots that they have made from the clay beneath their feet. There’s a lot of activity, and a lot of smoke! When completed, these pots and bowls will be taken to market to sell.

The area now called Highgate Wood was once part of the Bishop of London’s woodland holdings. The City of London took over management of the Wood in 1886, with a commitment to maintain it ‘in perpetuity for the benefit of Londoners’. The Wood is 28 hectares (70 acres) in size. Over 100,000 people visit each year to enjoy the calm and serenity of the place. It’s hard to imagine that it wasn’t always so peaceful!

In 1962, a field survey found a scatter of Roman pottery fragments on a ridge at the northern end of Highgate Wood. The archaeologists Tony Brown and Harvey Sheldon excavated a trial trench in summer 1966 which contained Roman pottery including many wasters (discarded remains of ceramic objects damaged or deformed during firing), pieces of baked clay and kiln fire-bar fragments – all suggesting pottery manufacture.

So, excavations began, and continued every summer until 1974, often with the help of local volunteers. Ten pottery kilns and pottery dating to between AD50 and AD160 were unearthed. Adult education classes on practical archaeology at the City Literary Institute and the Department of Extra Mural Studies at the University of London were involved in work on the finds.

The kilns

The potters built two types of kilns in Highgate Wood. These kilns produced a range of kitchen and table ware for Roman households.

Out of the ten kilns found, the earliest were dated 50 – 100AD. They were simple oval structures, built in ditches, with a single chamber and two flues (chimneys). They were used to fire pots of clay mixed with grog (a gritty substance).

The later kilns were an updraught type, with the heat from the fire drawn up through the firing chamber to a single flue at the top. These later kilns fired more sophisticated ‘sand-tempered’ clay ware that had been thrown on a wheel.

Kiln 2 was found during the first full season of excavation in 1967. This kiln was the most westerly of five kilns found amidst a substantial dump of fire-blackened debris, deriving from pottery production, towards the southern edge of an area of manufacture. It was also the only one of the kilns located which included a tiled flue.

The structural remains included the kiln's furnace, together with a central pedestal. Both parts were built of clay and there was evidence that pre-fired clay bars joined the top of the furnace walls with the top of the pedestal. The fire-bars created a floor for an oven above, on which the pottey to be fired in the kiln could be stacked in layers. A flue, crudely constructed from unmortared tiles, served to bring fire into the furnace. The roof and walls of the oven, which might have been temporary, built for each firing, hadn't survived.

Kiln 2 was excavated in 1968 and lifted from the site for conservation by the Horniman Museum as it was the best preserved of all of the kilns. The surviving top of the kiln lay only a few centimetres below the modern surface. Find out more about this kiln and plans to re-instate it at the wood here.

Pottery found associated with Kiln 2 included decorated beakers and jars. It also revealed examples of vessel forms not found anywhere else on the site, and probably of a slightly later period. It's therefore possible that Kiln 2 was the last of the kilns constructed in Highgate Wood, bringing to an end this long, intermittent period of pottery manufacturing.

The pottery and other finds associated with the kilns are now deposited at The Museum of London.