Waterside Viaduct

I suspect that whilst most people have heard of the famous Settle to Carlisle railway line, the Ribblehead Viaduct is rightly a national treasure - very few have heard of the the Ingleton Branch* line  which ran to Tebay to meet the main West Coast line and that was originally intended to form the main route between London and Scotland.
From even before its construction the plan was beset with problems and rivalries - in the mid 19th Century railway companies fought for the rights to build the stations and routes they wanted - there was little cooperation (hence for many years Ingleton had two railway stations) and no sense of a greater plan as perhaps we often assume nowadays. Whilst planning started in 1846, the line didn't open until 1861, and in those turbulent 15 years companies had merged, changed partners, and fatally for the Ingleton Branch - the Lancaster & Carlisle Railway Company got government backing for an alternative line between Sedbergh and Low Gill.

The line thus only ever really operated as a local connection, and like many it did not survive the rise of road transport and closed to passengers in 1954. The last train ran in 1964 and the lines were lifted 3 years later.

Today it is a route of truly impressive beauty, but alas there is no real way of connecting it. The viaducts at Sedbergh, Waterside and Low Gill are all Grade II protected structures as is Rawthey Bridge.
I've blipped Low Gill before with its impressive 12 arch span, and I'm sure I will blip the others one day, but Waterside, designed by Locke & Errington and built by 1600 navvies is the one I like most. Its symmetry, the mix of iron and Penrith red sandstone and it's position all add up to make it a fantastic local landmark. And most people don't even know it's there.

*Throughout the planning stages it was known as the Orton Branch, until political difficulties between rail companies meant a change of name as each tried to 'claim' Ingleton.