Graving Dock No.2, Clarendon Quay, Belfast, Co Antrim, BT1 3AL

Graving Dock No.2 at Clarendon Quay, Belfast, is an early 19th-century masonry graving dock constructed by the Belfast Ballast Board. Built between 1820 and 1826 (opening in 1826), it was designed by Thomas Burnett and constructed by the contractor firm Henry, Mullins & McMahon under the supervision of David Logan. At 285 feet by 34 feet, it is slightly larger than the earlier Graving Dock No.1, which was built between 1796 and 1800, reflecting the growing size of shipping during the period. The dock remains in active use by Belfast Harbour Commissioners for the inspection, painting and repair of small vessels.

The dock is aligned east-west and positioned at right angles to the west side of Clarendon Dock, north of No.1 Dock. It has a sub-rectangular plan with a rounded west end and a lock gate at its east end providing access to and from Clarendon Dock. The north, west and south sides feature sandstone steps descending to the flat dock bottom, originally used to support timber props whilst vessels were in dock. Unlike No.1 Dock, these steps have sloped and deeper rises with wider treads towards the bottom. Inclined slides run down the sides for bringing equipment and materials to the dock floor during repairs; there are two such slides at the west end and one along the middle of each side. Alongside each slide is a flight of steps with single-bar metal handrails. The middle slide on the north side and one of the pair at the west end retain metal chain guards along the dock edge, though winches are no longer present. The middle stairs on both sides have been later modified with quarter-turn concrete balconies. Additional stairs descend at the east and west ends of the north and south sides.

At the seaward east end of the dock stands a pair of slightly curved timber lock gates. A cantilevered metal footway runs across the top of the gates on their outer faces, fitted with five-bar steel handrails on either side. These footplates provide access to threaded rods for operating two vertical sluices in each gate, used for filling the dock once a vessel is inside and the gates are closed. Each gate is closed by hand winch mounted on its dock side and opened by a corresponding winch on the seaward side. Unlike No.1 Dock, the chain connecting each winch to its gate is ducted through an underground culvert emerging below the water line on the dock side. The seaward side walls adjacent to the gates are constructed of coursed sandstone blocks with recesses to accommodate the gates and smaller recesses for the sluice gate mechanisms. Vertical slots at the outer ends of the side walls accommodate stop timbers that were dropped in place when the gates required attention.

A depth gauge calibrated in metres and decimetres is mounted on the dock. Safety railing comprises two detachable chains supported on slender cast-iron posts. Low cast-metal mooring bollards are positioned around the sides. Four swan-neck cast-iron lamp standards line the south side, originally gas-lit but now electrified, with an additional modern lamp standard at the southeast. In later years, the dock has been emptied by an electric pump housed in a small building just south of the east end.

The dock is situated immediately west of Clarendon Dock, which connects via lock to Belfast Lough. The former pump house, subsequently refurbished as offices for Laganside Corporation, stands parallel with the dock on its south side. The area south of the dock is paved with sandstone flags, whilst granite cobbles deck the north side. Several modern buildings have been erected beyond the north side. At the southeast end stands an 8.3-metre-high bronze and stainless steel sculpture entitled "Dividers" by Vivien Burnside, commissioned by Laganside Corporation and erected in 2002. A modern functioning pump house sits between the east ends of the two docks.

Clarendon Dock itself, a wet dock with a sea lock separating it from the tideway, was built seaward of the graving docks in 1850–51 by the Belfast Harbour Commissioners (successors to the Belfast Ballast Board), appearing on the 1858 Ordnance Survey map and subsequent editions. It is named after George William Frederick Villiers, 4th Earl of Clarendon, who served as Lord Lieutenant of Ireland from 1847 to 1852. In the late 1990s, the entrance walls to No.1 Dock were underpinned.

These two graving docks represent fine examples of 18th and early 19th-century dock technology and are of considerable industrial archaeological interest. Their relatively small scale reflects the size of vessels of their era, whilst the contrast between them—particularly in the detailing of side construction, lock gate shape, and gate-closing mechanisms—demonstrates the evolution of dock engineering. The establishment of these docks laid the foundations for Belfast's shipbuilding industry, which subsequently rose to international prominence through Harland & Wolff on the County Down side of the river.