Groudle Glen Viaduct

The Viaduct from the glen

Groudle Viaduct is a dramatic tall structure which spans the narrow, steep sided Groudle Glen north of Onchan. In addition to carrying the A11, it also carries the Manx Electric Railway as it winds its way north alongside the road. The structure was built by the railway company in 1894, primarily to carry the railway, but with provision for road traffic as well. It consists of three tall and narrow stone arches, with a substantial protruding abutment on the north side of the glen. The small river passes through the central arch, with a footpath passing under the southern arch, forming part of a network of paths through the glen. It appears that prior to the construction of the railway, there was no road here, certainly the 1870 OS Six Inch Map does not show one.

As originally built, the bridge had matching parapets, creating a castellated appearance, with slightly raised sections over either abutment. However, the curvature of the railway over the bridge, particularly at either end, leads to a severe constriction in the width of the roadway. In order to try and improve this, the downstream parapet has been removed, the footway cantilevered a little over the face of the bridge, and fully cantilevered with additional triangular supports at each abutment. This has helped to improve the width of the road, but the white centre line is still very optimistic at each corner.