Dean Bridge is an impressive piece of engineering, but that is of little surprise as it was built by no less a man than Thomas Telford. Constructed to better connect the New Town to the historic core of Edinburgh it has to span the deep and narrow Dean Gorge, through which the Water of Leith flows. Far below the roadway, on the banks of the river, a few of the old mills that once lined the banks are still found, and this industrial area was also bypassed for the new fashionable residents of the New Town.
The bridge is an interesting structure, which some people may consider to have been widened at some point. However, apart from the parapets being raised in 1912 to reduce the risk of suicide attempts, the bridge has not been changed since completed in 1832. The most striking feature is the double arch in each of the four spans. The piers rise to large semi-circular arches, with tiny flanking piers on the outside providing support for secondary facing arches of a shallower design. These support the pavements and can be considered as similar to the cantilevered footways added to many bridges in the last century or so.
Of the four arches, only the central two seem to span the river, with the central pier sitting on a small island in the river. These piers are all hollow, to save weight and cost. The bridge was originally designed as a three span structure, avoiding the riverbed completely but problems with foundations led to a re-design. This also eliminated the decoration originally intended for the spandrels and an early design for castellated approaches - a gatehouse - were also abandoned, doubtless to keep to a budget.
The bridge today carries the main A90 road into the heart of Edinburgh on a reasonably wide S2 roadway, flanked by wide pavements. It is difficult, even from the river, to get a full view of the bridge due to the tall trees in the gorge and unfortunately, the heightening of the parapets a century ago has resulted in the impression of a bridge being lost to most motorists, as they cannot see over the parapets. This is a shame, as this impressive structure deserves more recognition.