This bridge is a viaduct on the Glasgow and South West Railway. John Millar designed the whole line with much repetition of detail and general construction. For example, the rolled string course forming a colossal drip check is common to all the bridges.

This bridge is a small, but significant, part of a substantial viaduct. It displays some interesting features. It is a large span shew bridge, its width being considerably greater than its span. The bridge is also wider on the left hand (west) side than the right hand (east) side, forming a funnel shape in plan.

Here is one of the bravest designs I have yet seen. In Bethnal Green, a short walk east of the station is Morpeth St. The bridge has been refurbished but the road is now closed to traffic because vehicles kept driving into it. The bridge has a modest skew of about 30 but the most spectacular thing is the very flat arch.

I came across Pynes Bridge quite by accident. It is under the road and over a small river so it is hardly noticeable. These are some of the flattest parapets I have seen. A sign of a very robust bridge. The stone copings finish it well.

This skew bridge at Cowley Junction in Exeter has the distinction of having been designed by one William Froude. The reason for including a modest railway bridge here is that it tells us a great deal about what mid 19th century engineers thought about the way skew bridges worked.

The Exe bridge is a sad truncated thing compared with many of a similar age scattered around Britain, but it is at home and it does give the lie to the often heard statement that skew bridges were invented in the railway era.

Calva bridge is both magnificent and common in that it is a typical mid 19th century structure. That is to say it is a thoroughly engineered construction. The interest here lies in the fact that its foundations were severely damaged by floods in November 2010.

The main bridge crosses the Calder and was first built about 1342. It has pointed arches and was only wide enough to carry a single cart. It has been widened twice on the upstream side with segmental arches. It is a grade 1 listed structure.

There is a story that one abutment of this bridge moved dramatically when it was decentred, requiring a lot of expensive remedial work. The sag is visible so it seems likely that the story is true, but where did I see it?

Ballochmyle Viaduct, the largest arch on the British Railway system!

John Millar designed the Glasgow and South West Railway, which eventually was joined from Dumfries to Gretna Green to form an extension of the Settle Carlisle. Ballochmyle was a huge undertaking, but there are many big bridges on the line.

Designed by Stephen Ballard in 1843 to take a minor (no through) road over the Hereford to Gloucester Canal. If you want to go and see it you could stay with his great-grand-daughter at Old Country House. That's how I was introduced to this remarkable bridge.

On the A470, on the southern exit from Llanelltyd, the bridge crosses Afon Mawddach. It has been bypassed by a modern bridge which will surely be gone long before this one. It is a scheduled monument dated to the second quarter of the 18th Century.