"Clearance can be a real challenge for a truck driver. Especially inexperienced drivers of rental boxtrucks seem to be quite oblivious to the warning signs and flashing “overheight” warning lights at this railroad trestle in Durham, NC. So frequently do trucks crash into the 11-foot-8 clearance trestle, that the railroad company installed a crash beam in front of it. This massive steel I-beam bears the brunt of the impact, protecting the structure that supports this fairly busy railroad track. Believe it or not – they already had to replace the beam once!" Source: http://11foot8.com/about/