A keystone is the wedge-shaped stone at the apex of a masonry arch or typically round-shaped one at the apex of a vault. In both cases it is the final piece placed during construction and locks all th
Dropped keystone at Colditz Castle
Keystone from the palazzo Borgazzi (Milan, Italy)
Keystone much enlarged for decorative effect, and carrying a coat of arms, Barcelona
The York Minster Chapter House rib-vault ceiling with central and peripheral keystones
An arch is a curved vertical structure spanning an open space underneath it. Arches may support the load above them, or they may perform a purely decorative role. As a decorative element, the arch dat
Keystone (architecture)
…A keystone (or capstone) is the wedge-shaped stone at the apex of a masonry arch or typically round-shaped one at the apex of a vault. In both cases it is the final piece placed during construction and locks all the stones into…
A complex funicular model (Church of Colònia Güell by Gaudi, 19th century)
Arcades of Pont du Gard (Roman)
Separating arches in the St. Zeno church [de]