Royal Monmouthshire Royal Engineers

The Royal Monmouthshire Royal Engineers is the most senior regiment in the British Army, having given continuous loyal service to the crown since 1539 and is now part of the reserve forces of the Territorial Army.

It is not the oldest regiment in the British Army, this honour goes to the Honourable Artillery Company (1537) but that unit has not given continuous loyal service to the crown, having fought for Parliament in the English Civil War.

The regiment is also unique in having the word Royal appear twice in its name.

The regiment is headquartered at Monmouth Castle in Monmouth but has sub-units in Cwmbran, Cardiff, Bristol, Swansea and Birmingham.