Milecastle 38 also known as Hotbank was a milecastle on Hadrian's Wall close to Hotbank Farm grid reference NY77276813. The milecastle is most famous for for the joint inscription bearing the names of the emperor Hadrian and Aulus Platorius Nepos, the governor of Brittania at the time the Wall was built. The stone was found in two halves several years after one another, the left hand part was found in 1715 and the right hand part was found in 1829. The first two lines on the inscription read IMP CAES TRAIAN and HADRIANI AVG, which identifies the emperor Hadrian and the third the Legion. The next two lines read LEG II AVG meaning Second Augustan Legion which erected the plaque and APLATORIONEPOTELEGPRPR that is refering to governor at the time Aulus Platorius Nepos.
The milecastle was excavated in 1935 and found to be 18 metres east-west by 15 metres north-south. It was found to have a short axis, with a Type I gateway. Pottery finds indicated an occupation of the 4th century. There was a rectangular building in the south-west corner and a causeway, 3.6 metres wide, to the east. A tombstone was found, inscribed "...us.. xit annis... mensibus du...ebus quinque", re-used as a pivot stone in the south gateway.
No visible remains can be seen at the location of milecastle 38.