`Haynes Buildings' Dry Dock and Gwndwn-Cadi Colliery Railway (720m south-west of Clydach Aqueduct, 7,952m from Swansea Basin) DD8, T24. George Haynes' colliery boats were based at a wharf where boats were built and a later maintenance dry dock was situated. Colliery and canal workers were housed in the southernmost terrace of the gothick Ynys-tanglws Buildings standing on the landward side of wharf facing the canal. A northern block of buildings formed the mansion of the prominent Swansea industrialist George Haynes.

This 'picturesque' development with extensive canalside orchards and gardens was originally known as 'Haynes Buildings' when built in c 1803, partly on the old waste-tips formed by canal construction. Haynes's workforce almost certainly serviced the trade to his colliery in Cwm Clydach, accessible by the railway joining the canal immediately to the north of this complex. Later a cable- and horse-worked railway was built directly up the steep hillside from the south side of the site to service two colliery-tunnels, probably by Haynes's successors on the site, Samuel & John Hill and John Strick, who also built the dry dock and operated the adjoining Clydach Foundry.

Later in the nineteenth-century a steam-tug was used to pull as many as 18 boats down the 7,640m lockless pound to Maliphant Lock (Lock 4) in Swansea,1 a hinged funnel enabling it to negotiate the low bridges. The tug was housed in a covered dock at right-angles to the canal, on the north side of the mansion gardens.

The later colliery railway ran on an incline, then under Heol Dywyll, to two colliery tunnels. It continued northwards to Gwndwn Cadi Slant (an inclined tunnel) engine-house on the slopes of Mynydd Gelliwastad. The line was still operational in 1876.2 Heol Dywyll crossed the railway over a small arched inclined tunnel of coursed rubble sandstone. The line of the railway is fairly easy to trace from the site of the colliery down to the valley road. Beyond this is cleared ground. Except for remains of the rubble sandstone support for the tipping platform by the site of the canal - a blank wall which was some 2.5m to 1.5m high. The remains of the approach embankment were a similar height.

Railway from canal at SN 6847 0059 to
Colliery tunnels at SN 6816 0110 and SN 6824 0088.
Dry Dock at SN 6848 0062).

1. v.i. Jack Phillips of Glais (son of one of the boatmen).
2. O.S. 1/10,560, Gl. Sh. 15, 1876-7.

Stephen Hughes, 16.08.2006