The site is known as Blackgrounds because of the color of the soil. It is in a field near what is now Chipping Warden, on the Northamptonshire-Oxfordshire border, but thrived under Roman rule during the 1st Century. An Iron Age village rested on the site 400 years before that, as evidenced by the discovery of nearly three dozen roundhouses and a road dating to that time.

Dominating the settlement was a Roman road 10 meters in width–nearly triple the usual width. Archaeologists said that the settlement must have been a trading center. Also found were kilns, workshops, glasswork, pottery, jewelry, and a few hundred Roman coins. Although the overall color of the soil is dark, archaeologists found some areas of soil the color of fire and concluded that it was the site of occupations that required burning, such as metalwork or breadmaking. Other evidence of commerce included the discovery of traces of galena, a mineral used for face makeup.

Archaeologists have been working at the site for more than a year. The site is one of several discovered in recent years during the progression of the High Speed 2 railway route from London to major cities in northern and central England.