Allensford Blast Furnace, on N. Bank of R. Derwent 250 Metres East of Bridge

The Allensford Blast Furnace, located on the north bank of the River Derwent, dates from the late 17th century or early 18th century. It is constructed from neatly squared stone, while the calciner is made of coursed stone. The furnace itself is a ruinous square structure featuring jambs and part of a round arch, with walls capped temporarily with concrete at the time of the survey. Further up the bank, the calciner has splayed wing walls flanking a round-headed arch that leads into a circular kiln, with parts of the kiln wall standing up to 3 metres high.

This site is an important industrial monument, traditionally linked to the sword makers of Shotley Bridge. The last use of the charcoal-fired blast furnace has been archaeomagnetically dated to between 1740 and 1750. Excavations conducted by Newcastle University in 1977 and 1978 provided further insights into the site.