DPS3249452: Narrow Water Castle, Co. Down, Ireland (photo) / Bridgeman Images

DPS3503628: Malahide Castle, Co Dublin, Ireland; 12Th Century Castle (photo) / Bridgeman Images

DPS3503715: Ballintubber Abbey, Co Mayo, Ireland; Mass Has Been Said In The Abbey Continually Since 1216 (photo) / Bridgeman Images

DPS3249409: Abbeyknockmoy, Cistercian Abbey Of Knockmoy, Co. Galway, Ireland (photo) / Bridgeman Images

MAA2956831: The Lady Chapel and Apse of Bourges Cathedral, 1899 (w/c on paper), Rooke, Thomas Matthews (1842-1942) / Bridgeman Images

STC156420: Interior decoration of houses represented in manuscripts of the 15th century, from 'Monuments Francais', printed by Amedee Peree, 1839 (litho), Willemin, Gabrielle (19th century) (after) / Bridgeman Images

UIG801510: The Qutub Minar, in Delhi, India. This 72.5 meters tall brick minaret, built in 1193 by Muslim Emperor Qutub-ud-din Aibek to commemorate the capture of Delhi, is notable for being one of the earliest and most prominent examples of Indo-Islamic architecture. It is surrounded by several other ancient and medieval structures and ruins, collectively known as Qutb complex. The complex is listed as a UNESCO World Heritage Site. It is one of the most popular tourist destinations in Delhi. February 4, 2010. (photo) / Bridgeman Images

HGP362710: Tantallon Castle (photo) / Bridgeman Images

HGP362708: Tantallon Castle (photo) / Bridgeman Images

HGP362709: Tantallon Castle (photo) / Bridgeman Images

SAP491862: Pena National Palace, Sintra, Portugal (photo) / Bridgeman Images

DGA574514: Austria, Vienna, facade of House of Teutonic Knights in Singerstrasse, where Wolfgang Amadeus Mozart lived for few weeks in 1781, engraving by Johann August Cirvinus / Bridgeman Images

HGP440054: Entrance to the Quadrangle, King's College, Old Aberdeen (photo) / Bridgeman Images

TRK7144420: Menorca, Alaior. Torre d'en Galmés talayotic settlement. / Bridgeman Images

MEP852241: Prefecture Palace in Ancona (Palazzo della Prefettura di Ancona), 14th Century / Bridgeman Images

TRK7144419: Menorca, Alaior. Torre d'en Galmés talayotic settlement. / Bridgeman Images

MEP852267: Prefecture Palace in Brescia (Palazzo della Prefettura di Brescia), 13th Century / Bridgeman Images

SZT5978807: King Cyrus riding on the bear, main facade, St Peter's Cathedral, Regensburg, 14th century, 20009 (photo) / Bridgeman Images

UTD2843498: Freiburg, Schwabenturm / Bridgeman Images

TRK6356041: Spain, Castile and Leon, Valladolid province, Peñafiel Castle (10th-15th centuries), Detail of one of the turrets which crown the building / Bridgeman Images

TRK697269: Spain. Collegiate Church of Cenarruza. 14th -15th centuries. Exterior. Basque Country. / Bridgeman Images

XJF451328: Belmont Castle, near Grays Thurrock, Essex, engraved by Henry Wallis, 1832 (engraving), Bartlett, William Henry (1809-54) (after) / Bridgeman Images

GRL5974087: The "Capital of the Judge" or "of the Upright Judge and of the Corrupt Judge", work by Campionesi masters, XII - XIII century, Torresani Hall, Ghirlandina Tower, Modena, Italy (photo), Torresani Hall, Ghirlandina Tower, Modena, Italy (photo) / Bridgeman Images

GRL6372545: Genoa, Duomo (St Lawrence Cathedral), West side, the façade, the main doorway, left jamb, corbel: "Ecclesia feeding the Apostles Peter and Paul and two angels", by Master of the Ark of the Baptist, about 1225 / Bridgeman Images

DPS3256052: Wexford,Co Wexford,Ireland;Selskar Abbey (photo) / Bridgeman Images

DPS3250338: Carlingford Castle, Co Louth, Ireland (photo) / Bridgeman Images

DPS3254035: Tintern Abbey, Co Wexford, Ireland; Two People Leaving An Abbey Founded In 1131 (photo) / Bridgeman Images

HGP380433: Drumlane Abbey round tower, County Cavan, Ireland (photo) / Bridgeman Images

SLR3823981: Wells Cathedral / Bridgeman Images

DGA2573078: Trakai island castle, 15th century, Lake Galve, Lithuania / Bridgeman Images

DGA911183: Christ Blessing, wooden statue in Sainte-Chapelle (The Holy Chapel) (13th century), Paris (Unesco World Heritage List, 1991), Ile-de-France, France / Bridgeman Images

TRK879335: Coat of arms of Pope Alexander Vi. Castle Sant'Angelo. Rome. / Bridgeman Images

DGA1129800: Municipal tower or belfry, 9th-14th century, Forli, Emilia-Romagna, Italy / Bridgeman Images

DGA1131107: Porticoes of Piazza Cavour with Tower of the Angel (14th-15th century) in background, Vercelli, Piedmont, Italy / Bridgeman Images

DGA756068: Detail from left section of Martyrdom of Saint Placid, fresco by Umbrian Master, 15th century, transept of Upper Church of Sacro Speco Monastery, Subiaco. Italy, 15th century. / Bridgeman Images

HIM5263103: Norwich Cathedral, Norfolk, c1870. Norwich Cathedral was founded by the Normans in 1096 and completed in the mid 12th century. The 315 foot high spire completed in 1480 is the second highest in England after Salisbury. / Bridgeman Images