Stained glass window by Lawrence Lee showing the Virgin Mary and Child flanked by St. Thomas and St. John the Baptist with a roundel of the church tower and kneeling figure of Christopher Wren below, South Chapel, St. Mary Aldermary Church, City of London, London, England, United Kingdom, Europe

Caligraphy Roundels Naming Hasan, grandson of Mohammed on left and Caliph Alion on right, with tourists viewing from the Gallery, Interior, Hagia Sophia Grand Mosque, 537 AD, UNESCO World Heritage Site, Sultanahmet, Istanbul, Turkey, Europe

Cultural Village, Johannesburg, South Africa, Africa

A London Underground sign at Kings Cross, London, England, United Kingdom, Europe

Woman selling non bread, Siyob Market, also known as Siab Market, Samarkand, Uzbekistan

Non bread for sale, Siyob Market, also known as Siab Market, Samarkand, Uzbekistan

Rice paper circles drying outdoors on a bamboo lattice drying frame, Cuu Long, Cai Be, Mekong Delta, Vietnam

Non bread for sale, Siyob Market, also known as Siab Market, Samarkand, Uzbekistan

Stained glass roundel depicting St Vincent being consoled by angels, made between about 1225-1250 by a French artist, Stained Glass Museum in Ely Cathedral, Ely, England, United Kingdom, Europe

Stained glass roundel depicting St Vincent on the gridiron, made between about 1225-1250 by a French artist, Stained Glass Museum in Ely Cathedral, Ely, England, United Kingdom, Europe

Stained glass roundel surrounded by quarries, depicting a fox and a goose, a scene from Reynard and the fox, designed and made by Clement James Heaton between about 1845-1855, Stained Glass Museum in Ely Cathedral, Ely, England, United Kingdom, Europe

Busts at the first roundel in Sanssouci Park, Potsdam, Brandenburg, Germany, Europe

Busts at the first roundel in Sanssouci Park, Potsdam, Brandenburg, Germany, Europe

Busts at the first roundel in Sanssouci Park, Potsdam, Brandenburg, Germany, Europe