As a result of recent road improvements, two examples of a hitherto unknown type of iron-working furnace have been found in Northamptonshire. These are at Laxton Lodge (SP068971) and Byfield (SP505515), at different ends of the county (FIG. I). Most Romano-British furnaces belong to the shaft type which has a maximum diameter of 0–5 m. The more recently found furnaces are between 1–1.4 m in internal diameter which means that the method of working them must have been quite different from the smaller shaft furnaces.

The site of Roman Bannaventa, formerly mentioned as a stopping-place in the British routes of the Antonine Itinerary, straddles the boundary between the Northamptonshire parishes of Norton and Whilton along the line of the modern A5, or Watling Street (FIG. I). Although its general position to the west of Whilton Lodge could be inferred from the local discovery of Roman objects and associated building remains recorded from the early eighteenth century onwards, its precise site was only identified in summer 1970. In that year, air reconnaissance revealed the outline of part of a large, defended enclosure to the west of the modern trunk-road which diverges slightly eastwards from its Roman predecessor. Subsequent investigations, described here, indicate that the enclosure lay awkwardly across the original road which passed through its western half. The defences form an irregular quadrilateral with broad, rounded corners which enclose an area of between 4–4·5 ha approximately centred upon NGR SP 612645 (FIG. 2). The position of the settlement, at the southern end of a raised tongue of glacial sand and gravel between 110–120 m above Ordnance Datum, corresponds closely with the suggested place-name meaning of ‘market on the spur’ or ‘prominent field’, and it may be unnecessary to insist that the name was transferred from the nearby hillfort at Borough Hill, Daventry.