Bifrost, abatis, advanced work, balistraria, bank, banquette, barbed-wire entanglement, barbican, barricade, barrier, bartizan, bascule bridge, bastion, bateau bridge, battlement, breastwork, bridge, bulwark, cantilever bridge, casemate, catwalk, cheval-de-frise, circumvallation, contravallation, counterscarp, curtain, demibastion, dike, earthwork, enclosure, entanglement, escarp, escarpment, fence, fieldwork, floating bridge, flyover, footbridge, fortalice, fortification, gangboard, gangplank, gangway, glacis, lift bridge, loophole, lunette, machicolation, mantelet, merlon, mound, outwork, overbridge, overcrossing, overpass, palisade, parados, parapet, pontoon bridge, portcullis, postern gate, rampart, ravelin, redan, redoubt, rope bridge, sally port, scarp, sconce, span, stepping-stone, stepstone, stockade, suspension bridge, swing bridge, tenaille, toll bridge, vallation, vallum, viaduct, work