Forth Bridge, Scotland

Opened in 1890 by the future King Edward VII, this is the world’s first major steel structure and represents a key milestone in railway civil engineering.

During construction, workers built a toilet over the water and boats would sometimes pass underneath! The “preserved” cubicle with no plumbing, no door and just a hole cut into a wooden bench is 155ft above the choppy Forth of Firth.

“Painting the Forth Bridge” is used as an expression of a neverending task, based on the assumption that at one time in the history of the bridge, repainting commenced immediately on completion of the previous paint job. It was last painted in 2011 and it’s now expected to last 25 years.

Immortalised in Alfred Hitchcock’s The 39 Steps, Iain Banks’s novel The Bridge, the posters for Irn Bru, as well as featuring in the opening ceremony of the Glasgow 2014 Commonwealth Games, it is also a UNESCO World Heritage Site.

Not to be confused with the Forth Road Bridge, it was the longest single cantilever bridge in the world and continues to operate as a rail route between Edinburgh and Aberdeen with up to 200 trains crossing its 8,094ft length every day. theforthbridges.org