11 Arthur Street, Hillsborough, County Down, BT26 6AP

11 Arthur Street is a Victorian mid-terrace single-storey workers cottage with attic, built around 1850 to house workers and tenants of the Downshire Estate. It is located on Arthur Street off Ballynahinch Street, north of St Malachi's Parish Church in Hillsborough, and forms part of a pair of matching terraces that line the street.

The building is rectangular in plan with a modern rear extension. The roof is pitched natural slate with clay ridge tiles, topped with two dormer windows and cast-iron rainwater goods. A brick chimneystack shared with the adjoining building has two clay pots. The walling is coursed rubble masonry with red brick and sandstone surrounds to doors and windows. A distinctive sandstone elliptical arched alleyway with long-and-short surrounds is shared with the adjoining dwelling; this was formerly the access to the rear yard and now provides secondary access to the modern extension.

The front elevation faces east and is asymmetrically arranged with a ground floor window on the left of the front door, which is a replacement timber sheeted door painted yellow. The windows are modern top-hung double-glazed timber casements painted white with lattice lead applied to the face, sandstone cills, and robust half-circle sandstone label moulding. The alleyway features matching label-mould over its entrance. The left elevation abuts the adjoining dwelling (number 13). The right elevation forms part of the passageway between number 9. The rear elevation is abutted by the modern extension.

Historically, Arthur Street was developed in stages throughout the first half of the 19th century. The earliest houses, shown on the 1833 Ordnance Survey map, date from the 1820s and were erected to accommodate workers and tenants of the Downshire Estate. By 1834 the town plan identified six dwellings on the street. By the second edition Ordnance Survey map of 1858, the remainder of the street as it appears today is shown. The earliest part of the street was constructed using random rubble masonry with granite moulding and arched alleyways. A second phase of construction introduced sandstone in place of granite, with walling of squared galletted rubble; the later part constructed around 1850 features more regular cut stone laid to courses. Number 11 appears to be part of this later phase of construction.

According to Griffith's Valuation of 1862, the owner was John Smith and the house and yard were valued at £2 15 shillings. The valuer noted that the rents were 'moderate'. The house claims ownership of a passageway and has an additional bedroom located over it, which accounts for its valuation being slightly higher than the neighbouring house. All houses on the street were originally provided with a rear yard containing a pit for household waste and a dry toilet. Coal was typically stored in a hole under the stairs adjacent to the living room, and water was supplied from either a tap at the top of Arthur Street or a pump at the end of Wapping Street.

The building retains its original modest style, proportions, and façade with dressed stone archway and stone hood mouldings, constituting an important part of the overall character of Arthur Street. However, many original materials have been replaced during recent renovations. The building was listed in 1974 and has undergone various 20th-century alterations and additions, including replacement of dormers in 1990 and the installation of skylights in 1999, which have contributed to the loss of original features. The building is situated within a conservation area.