The deck is 2 pieces of ally angle 3? x 1? 2.7m long it was the cheapest way of doing it and got it from a ally stockholders in the UK. The flat strips are as someone said courtesy of Bricomarche, but they ran out so awaiting fresh supplies.
The bridge piers are thermalite blocks awaiting some stone carving.
The Bridge is loosely modelled on the 'Pont Gisclard ou de La Cassagne' in France, where else. so there is a prototype.