string course

Upper cover of the spandrels and also sideways border of the footpath. Sometimes cantilevers because of design and protection of the spandrels against weather.

railing

Among a parapet the usual anti-fall guard. Railings are later added to arch bridges, sometimes in exchange for a parapet.

wingwall

Sidewalls (parallel or skew to road) to support backfilling of the slope, are passing towards arch into abutments. Some with a slight battering (inward slope).

spandrel

The sidewise walls over the voussoirs. The spandrel follows at base the course of the vousoirs, so has the maximum height at the abutments and the minimum height at the crown. The spandrels are vertical built.

voussoirs

Sidewise arch ring under the spandrel, often built of superfine dressed stone. The keystone (stone at the top of the arch) is sometimes well styled by the stonemason. The voussoirs are running parallel to arch rings at the underside of the arch and are bondet with them.

arch

The arch is the properly supporting part of the bridge. It starts at the impost and is running mostly as half-circle to the crown. Sidewise it is bounded by the arch ring.

abutment

The abutmnent is formed by the open case of the impost and the high part of the spandrel.

raking wing walls

This bridge does not only have (high) parallel wing walls, but also added little raking wing walls. They were nessesary because of the quite high abutments.

crown

This is the top (highest intended) line of the arch. Outside passes the crown into the voussoirs with the keystones.

impost

The impost are laying on the abutments / foundation und are the lower line of the arch and the passing into the abutments or at smaller bridges directly into the foundation.

foundation

Groundwork of the bridge, sometimes is the in-situ rock enough as natural foundation.