Road and rail may be segregated so that trains may operate at the same time as cars (e.g., the Sydney Harbour Bridge).
The rail track can be above the roadway or vice versa with truss bridges.
[43] Railway Track under Metro Bus Track on Gate of Rawalpindi City near Marirh Chowk Muree Road Rawalpindi The Bernina railway shares a bridge over the River Poschiavino at Campocologno just north of the Swiss-Italian border.
Both railways operated by Aare Seeland Mobil go over three combined bridges each.
During wartime and other emergencies, rail tracks on bridges are sometimes paved to allow road traffic to proceed.