Complex sentence: The route includes many bridges, viaducts and tunnels--the railway is expected to cross a total of over 750 bridges and pass through over of tunnels, the longest of which is about in length.
Split into simpler sentences: The route includes many bridges, viaducts and tunnels. The railway is expected to cross a total of over 750 bridges and pass through over of tunnels, the longest of which is about in length.