I designed this bridge with Tinkercad, and use eight of them (one is movable) in a model of the Seven Bridges of Königsberg for the Mathamuseum.
FWIW, our ball chain climbs over the walls, and I have had to add escutcheon pin bollards. My bridges would be improved by adding posts or more abrupt ends.
Printed with supports using Slic3r for Prusa in PETG.