16 Castle Street, Glenarm, Ballymena, Co Antrim, BT44 0AT

This is a plain, two-storey rendered end-of-terrace house, one of a pair of largely identical neighbouring properties built in 1830, situated on the south side of Castle Street at its junction with Lower Castle Street in Glenarm.

The north-facing front elevation is asymmetrical. On the ground floor, a plain sheeted timber door sits to the left, topped by a shallow plain rectangular fanlight. To its right are two 6-over-6 sash windows. The first floor repeats the same arrangement directly above, with two similar but shorter sash windows. Above the front door is a small carved stone plaque inscribed "These two houses were built by Adam Ellison in A.D.1830". The right-hand side of the front elevation has plain rendered quoins. The west-facing gable is largely blank apart from two fixed windows evenly spaced at first floor level and a conservation-area-style electric street light fixed to the centre of the wall at first floor height, which is gas-lantern in appearance but electrically powered. The façade is finished in roughcast. The gabled roof is slated, with a brick chimneystack to the east side of the ridge and a plain rendered stack to the right. Cast iron rainwater goods serve the north elevation; PVC goods serve the south.

To the rear, a full-width flat-roofed single-storey return projects from the ground floor of the south elevation. The west face of this return is blank, while the south face has French windows. At first floor level on the south elevation there are two widely spaced modern top-hung 6-over-6 windows.

Some original interior period detail survives, which alongside the building's group value and townscape importance forms the basis for its continued listed status.

This house and its immediate neighbour to the east, number 14, were both built by an Adam Ellison. By 1859 the property was recorded in the name of a Mrs Eliza Boyd but was unoccupied at that time.

Castle Street is the shortest of Glenarm's four main original streets, running westwards from the intersection of Toberwine and Altmore Streets to the bridge over the Glenarm River, with Lower Castle Street branching southwards near the western end. The street formed part of the historic main road from Larne, a route of possible medieval origin that wound northwards through The Vennel, across the bridge, and onwards to what is now the Straidkilly Road. The earliest surviving leases in the Antrim Papers relating to plots and buildings along the street date from 1711, though at least one building — the old parish church — was already standing at the south-west end of the street as early as 1683. The remains of a 13th-century Bisset castle, probably a tower house, are reputed to have stood at the north-east end of the street, and the still-extant former courthouse — believed to have been standing at least since the 1750s — is thought to incorporate part of its ruins. The bridge at the west end was erected in 1682, replacing an earlier ford, but had to be largely rebuilt in 1713 following flood damage. The street was originally known as Bridge Street, a name that appears to have persisted until the mid-19th century.

John O'Hara's map of 1779, the earliest surviving plan of Glenarm, shows the street fully developed on both sides, with a layout matching what appears on the Ordnance Survey map of 1832. Evidence from the 1859 valuation suggests that most of the buildings shown in 1832 are those standing today, with the short terrace in Lower Castle Street appearing around 1835 to 1840.

O'Hara's map clearly illustrates Castle Street's former pre-eminence as part of the main northward route from Larne, with the road skirting the grounds of Glenarm Castle on the west side of the river. In the early 19th century this changed significantly: the old road was superseded by the new Coast Road and the new Glenarm Bridge, built in 1813 at the north end of the village, and the castle grounds were enclosed. This process was complete by the mid-1820s and appears to have led to a gradual reduction in the street's status. It is perhaps telling that while a figure as notable as Lord Antrim's agent could be found living in Castle Street in the late 18th century, by the mid-1830s the agent had moved to the south end of the newly widened and considerably grander Altmore Street.