UDK839807: Spain, Seville, stone gargoyle of a face on thirteenth century tower, Torre de Don Fadrique. / Bridgeman Images

UDK836188: Italy, Apulia, Trani, Cathedral facade dominated by tall bell tower set against blue sky on seafront / Bridgeman Images

ELC849324: Rock of Monrupino, XV Century / Bridgeman Images

SGM489779: Château de Chillon, Lake Geneva, Switzerland (photo) / Bridgeman Images

XLF3789043: Traitor's Gate at the Tower of London, British School, (19th century) / Bridgeman Images

XIR217914: Left hand side of the church portal (stone) (b/w photo), Romanesque, (12th century) / Bridgeman Images

HGP362828: Walmer Castle (photo) / Bridgeman Images

JB148491: Relief of the south front of the Church of the Intercession of the Holy Virgin on the Nerl (photo) / Bridgeman Images

SCN3249114: View of the Cattedrale di San Vigilio, Duomo di Trento, Trento, Italy (photo) / Bridgeman Images

VLS938010: View of a Tower, San Gimignano (photo) / Bridgeman Images

PC991910: West end with Cosmati floor / Bridgeman Images

MES429107: Shop in San Gimignano, Tuscany, Italy (photo) / Bridgeman Images

MAE3469397: Funerary sculpture from the west door, Church of Saint-Pierre-es-Liens, Blérancourt, Nord-Pas-de-Calais-Picardie, Aisne, France (photo) / Bridgeman Images

MAE3469398: Detail of the west door sculpture, Church of Saint-Pierre-es-Liens, Blérancourt, Nord-Pas-de-Calais-Picardie, Aisne, France (photo) / Bridgeman Images

MES3470006: View of the Church of Santa Maria Assunta, Muggia, Friuli, Italy (photo) / Bridgeman Images

MAE3469547: Church of Saint Anne of Nohant, Nohant-Vic, Centre, Indre, France (photo) / Bridgeman Images

IMB4884228: Fortress of the Crusaders; medieval castle; Order of St. John; residential tower; Kolossi near Limassol; Southern Cyprus; Republic of Cyprus; Mediterranean Sea; Europe / Bridgeman Images

KWE268376: The Great Mosque, Cordoba, illustration from 'Spanish Pictures' by the Rev. Samuel Manning (engraving), English School, (19th century) / Bridgeman Images

MES3470010: Saint Catherine (fresco), Italian School / Bridgeman Images

DGA648167: France, La Brigue, Notre-Dame des Fontaines Chapel, People in medieval clothes, detail from Denial of St Peter, fresco, by Giovanni Canavesio, 1491 / Bridgeman Images

SZT1072818: Eulenspiegel with scales on a house facade in Garmisch-Partenkirchen, Germany, 2009 (photo) / Bridgeman Images

GCL3135000: CHARTRES CATHEDRAL St. Theodore and St. Etienne. Figures, 13th century, from the south portal of Chartres Cathedral, France. Photograph, mid-20th century. / Bridgeman Images

GCL3393500: IRELAND: CLOCHÁN A Clochán, a medieval dry-stone hut built by Irish Celtic monks, c.10th century A.D. / Bridgeman Images

DGA3935649: Broletto or Community Palace and buildings in Piazza Motta at night, Orta San Giulio, Lake Orta, Piedmont, Italy, Detail / Bridgeman Images

TRK563141: Monastery of Sant Cugat. Capital depicting Samson slaying the lion. Catalonia. Spain. / Bridgeman Images

TRK558870: Jesus and the Devil on the pinnacle of the temple. Codex of Predis (1476). Italy. / Bridgeman Images

DGA3938901: Bridges to place the artillery (A), gabions (B), watch tower (C), copperplate engraving from Diffesa et Offesa Delle Piazze, by Pietro Paolo Floriani, published by Giuliano Carboni, Macerata, 1630 / Bridgeman Images

DGA3938906: Handling of the earth during the construction of a fortification (tools and profiles), copperplate engraving from Diffesa et Offesa Delle Piazze, by Pietro Paolo Floriani, published by Giuliano Carboni, Macerata, 1630 / Bridgeman Images

DGA3938911: Fortified barracks (plan), copperplate engraving from Diffesa et Offesa Delle Piazze, by Pietro Paolo Floriani, published by Giuliano Carboni, Macerata, 1630 / Bridgeman Images

MAE340575: Detail of a capital depicting the death of a man (photo) / Bridgeman Images

LIT372474: View of Dhammayangyi Temple (photo) / Bridgeman Images

VLS938014: Palazzo Communale, Massa Marittima (photo) / Bridgeman Images

SNK1127936: Astronomical clock, Prague, Czech Republic (photo) / Bridgeman Images

KW3058330: Florence, Tuscany, Italy. The medieval Ponte Vecchio, or Old Bridge, on the Arno River. (photo) / Bridgeman Images

TRK3086427: Iran, Varamin, The Masjid-I Mosque, 1322, Decorative muqarnas vaulting (photo) / Bridgeman Images

MAE3469148: Puente Romano, Córdoba, Andalucía, Spain (photo) / Bridgeman Images