Thrapston Bridge and Attached Causeway (That Part in Islip Civil Parish) Thrapston Bridge and Attached Causeway (That Part in Thrapston Civil Parish)

Thrapston Bridge and the attached causeway, located in the civil parishes of Islip and Thrapston, is a Grade II listed structure. The bridge spans the River Nene and has medieval origins, with parts rebuilt and widened in the mid to late 18th century and restored in the 19th and 20th centuries. It is constructed of squared coursed limestone and limestone ashlar, with some sections restored using blue brickwork.

The east elevation features nine arches. The four arches on the left are medieval, double chamfered, and have two-centred heads, while the widened 18th-century arches have semi-circular outer shapes. The five arches in the center and to the right are likely from the 18th century, semi-circular in form, with a plain string course above the four arches on the right. All arches are adorned with orange brick dressings, and the two arches on the far right include panels of blue brickwork between them. There are four cutwaters with refuges between the center arches, and a plain parapet with chamfered ashlar coping.

The west elevation mirrors the east, featuring panels of blue brickwork on the left and two cutwaters with refuges between the center arches. Historical records indicate that in 1224, Bishop Hugh of Wells granted an indulgence to travelers who contributed to the bridge's repair, and in 1313, Bishop Dalderby granted an indulgence for the upkeep of the nearby Chapel of St. Thomas the Martyr. Grants for repairs were also obtained in the 14th and 15th centuries. In 1543, Leland noted a bridge with eight arches, and a repair brief from 1664 mentioned a bridge with 24 arches.