When I worked as a Plant Fitter I was asked to drive a mobile crane back to the yard. It was very heavy, and, with a fixed jib, quite tall. I had to take a route completely unknown to me. First stop was when I came across a low bridge I had no chance of fitting under. As I was trying to get cars behind me shifted so I could reverse back, a PC came along. He radioed in and got a car to come and help. They sorted my mess out, and told me to follow them to a suitable bridge, and gave me directions avoiding any further problems. This was in the Guildford area. Their directions got me to Windsor Great Park, which I knew, so didn't foresee any further problems. I had never realized just how many low and light load bridges there were around the yard area. With causing havoc at the sites of three bridges, I finally rolled into the yard after about five hours on the road. Not bad for what was usually an hour's drive.
PS. When I bought my first satnav, I discovered a website where you can download info on just about every bridge in the country as a POI. Guess who's had them on every satnav since.