Complex sentence: The railway crossed built-up Leicester on a 190ft wide Staffordshire blue brick viaduct, incorporating a series of fine girder bridges, which was in excess of a mile and a half in length, upon which Leicester Central station would be constructed.
Split into simpler sentences: The railway crossed built-up Leicester on a 190ft wide Staffordshire blue brick viaduct, incorporating a series of fine girder bridges. In total the viaduct was in excess of a mile and a half in length and it was upon this that Leicester Central station would be constructed.