The seismic vulnerability of regular bridges with continuous deck, monolithically connected to the piers or supported on elastomeric bearings is studied, as a function of the bridge length, the number, section and height of piers and the number of columns per pier. At the abutments the deck is free to translate longitudinally; transversely it is either free or constrained. Prototype bridges are designed according to Eurocodes 2 and 8 (EC2 and EC8) and their fragility curves constructed as a function of peak ground acceleration. Their seismic deformation demands are estimated by 5%-damped linear analysis and their shear forces from the plastic mechanism. Bridges designed to EC8 have satisfactory fragilities; those designed to EC2 alone show remarkably good seismic performance, yet quite higher fragilities than the bridges designed to EC8. Horizontal displacements are critical for long bridges or bridges on bearings. Hollow piers are vulnerable in shear.