It is one of the best preserved examples of a medieval barbican in Europe and is designated as a protected national monument. It consists of two towers, each with four floors, joined by a bridge at the top and an entrance arch at street level. Entry is gained up a flight of stairs in the south tower. There is a slot underneath the arch from where a portcullis could be raised and lowered.
Historians have wondered why such an enormous barbican was built here in the east of the town, when the main artery through the town has always been north/south. For example, a similar barbican in Canterbury is less than half the height of Laurence's Gate. However, from the top of the Gate, the estuary of the Boyne and the four mile stretch of river from there to Drogheda can be clearly observed. This is the only point in the town with a clear view of any potential sea invasion. This is proposed as a reason why Laurance's Gate was built to such a height.
A portion of the town wall remains to the south of Laurence's Gate. North of Laurence's Gate, the wall ran up Palace St/King St where the footpath is today. The depth of the basements of the houses and school suggest the presence of a steep trench outside the wall. Over the centuries, as the walls and gates fell into disrepair, the rubble stones were reused in later buildings. For example, the house and walls at the corner of Laurence and Palace St and stone walls in Constitution Hill. Old pictures show that a toll booth and gate house remained until the early 1800s. The shop beside Laurence's Gate was a bicycle shop 100 years ago. The green letter box dates from a time when there was a post office there.