A colorful alley full of flowers at blue hour in Gubbio, Umbria, Italy, Europe

Jerpoint Abbey, County Kilkenny, Leinster, Republic of Ireland (Eire), Europe

Wall Reliefs, Temple of Sobek and Haroeris, Kom Ombo, Egypt, North Africa, Africa

Facade of Il Santo (Basilica di San Antonio) with Donatello`s Monument to Gattamelata, Padua, Veneto, Italy, Europe

City Wall, originally built in the 12th century, Avila, UNESCO World Heritage Site, Castile and Leon, Spain, Europe

Entallada Lighthouse, Fuerteventura, Canary Islands, Spain, Atlantic, Europe

Towers and Kremlin Wall, Rostov Veliky, Golden Ring, Yaroslavl Oblast, Russia, Europe

Palamidi Fortress, Old Town of Nafplio, Argolis, The Peloponnese, Greece, Europe

Giglio Island, Tuscany, Italy, Europe

Old Town Walls, Cartagena, Bolivar Department, Colombia, South America

The Badaling section of the Great Wall of China in winter, UNESCO World Heritage Site, Badaling, China, Asia

Exterior of the theatre, Vienne, Rhone Valley, France, Europe

Baboon, Abha, Kingdom of Saudi Arabia, Middle East

Fence posts in salt grass, Hope, Alaska, United States of America, North America

St. Coloman Church, Schwangau, Bavaria, Germany, Europe

Moata Lake and the fort, Amber, near Jaipur, Rajasthan State, India, Asia

View of Llyn Gwynant Lake, Snowdonia National Park, North Wales, United Kingdom, Europe

Street in the souk, Marrakesh (Marrakech), Morocco, North Africa, Africa

Saint Peter and Saint Paul's Church, famous for its statues of the Apostles, Grodzka Street, Krakow (Cracow), UNESCO World Hertitage Site, Poland, Europe

View the original wall around the town of Visby, UNESCO World Heritage Site, Gotland Island, Sweden, Scandinavia, Europe

Spring alpine flower meadow and mountains, Grindelwald, Bern, Switzerland, Europe

Sunset on a watch tower on the wall of the Forbidden City Palace Museum, Beijing, China, Asia

Ming Dynasty city wall ruins, Beijing, China, Asia

Small boat and traditional house at Playa Pozo Negro on the volcanic island of Fuerteventura, Canary Islands, Spain, Atlantic, Europe

Monk in saffron robe sitting on wall with his cell phone in hand, Royal Palace, Mandalay, Myanmar (Burma), Asia

Plaza del Duomo (Cathedral), Cefalu, Sicily, Italy, Europe

Colourful street sign, Montevideo, Uruguay, South America

The City Walls (Ciudad Amurallada), UNESCO World Heritage Site, Cartagena, Colombia, South America

Western Wall or Wailing Wall with worshippers, Jerusalem, Israel, Middle East

Western Wall (Wailing Wall) with worshipper and prayer slips, Jerusalem, Israel, Middle East

The wall of Ston, Peljesac Peninsula, Croatia, Europe

A view of a waterfall on the steep wall of mountains with the Myklebustbreen glacier at the top, Vestland, Norway, Scandinavia, Europe

City ramparts and Parc de la Mar, Palma de Mallorca, Majorca, Balearic Islands, Spain, Mediterranean, Europe

Chester Roman Gardens, Chester, Cheshire, England, United Kingdom, Europe

Chacma baboons (Papio cynocephalus ursinus) playing, Kruger National Park, Mpumalanga, South Africa, Africa

The Great Wall of China at Badaling, UNESCO World Heritage Site, China, Asia

Old Port Canal, fishing boats and wall of the Kasbah, Bizerte, Tunisia, North Africa, Africa

Old abandoned housing on Samson, Isles of Scilly, United Kingdom, Europe

Stone walls, Samson, Isles of Scilly, United Kingdom, Europe

City Ramparts, Tuscania, Viterbo province, Latium, Italy, Europe

Doge's Palace, St. Mark's Square, Venice, UNESCO World Heritage Site, Veneto, Italy, Europe

Swimmers and sunbathers on rock wall next to Rab Town, island of Rab, Kvarner region, Croatia, Europe

San Juan des los Reyes Monastery and town wall reflected in the Tajo River, Toledo, Castilla-La Mancha, Spain, Europe

Kremlin Wall with Towers, UNESCO World Heritage Site, Veliky Novgorod, Novgorod Oblast, Russia, Europe

Entallada Lighthouse, Fuerteventura, Canary Islands, Spain, Atlantic, Europe

The Roman Agora, UNESCO World Heritage Site, Delphi, Phocis, Greece, Europe

Ball Court, in the archaeological site of the Maya civilization, at Copan Ruins UNESCO World Heritage Site, Copan, Honduras, Central America

The Stelae P carving at Copan Ruins, UNESCO World Heritage Site, Copan, Honduras, Central America

Towers of the town wall, from outside, Tallinn, Estonia, Baltics, Europe

View of Vianden and Our River, Vianden, Luxembourg, Europe

Colourful colonial architecture in Jerico, Antioquia, Colombia, South America

The Guannock Gate in The Walks, King's Lynn, Norfolk, England, United Kingdom, Europe

Medieval frescos on wall, David Gareja Monastery complex, Sagarejo Municipality, Kakhetia, Georgia, Central Asia, Asia

Cod drying on a wooden pole in Reine, Moskenesoy, the Lofoten Islands, Norway, Europe

The harbour, Otranto, Apulia, Puglia, Italy, Europe

Old Town Walls, Tarragona, Catalonia, Spain, Europe

Peeling painted wall depicting women collecting water from the pump on village walls, Raghurajpur, Orissa, India, Asia

Skeins of washed spun raw silk hanging to dry along a village house wall, Naupatana village, Orissa, India, Asia

Bastion of the Vilnius Defensive Wall, Old Town, Vilnius, Lithuania

A rock spire separate from the cliff wall west of Zuni Point at Grand Canyon, Grand Canyon National Park, UNESCO World Heritage Site, Arizona, United States of America, North America

Sea walls of the Old City of Akko, Israel

View of building and street signs on wall in Chinatown, Port Louis, Mauritius, Indian Ocean, Africa

Buddha statue in the courtyard of Bruneck Castle, Sudtirol (South Tyrol) (Province of Bolzano), Italy, Europe

Ksiaz castle, Sudeten mountains, Silesia, Poland, Europe

Crinoid from the Family Mariametridae, in the shallow reefs off Freewin Wall, near Waigeo Island, Raja Ampat, Indonesia, Southeast Asia, Asia

A rickshaw passing a wall sign celebrating Cuban freedom, Havana, Cuba, West Indies, Central America

Summer dawn, Corfu Town fortifications and harbour from the sea, UNESCO World Heritage Site, Corfu, Ionian Islands, Greek Islands, Greece, Europe

Worshipper at The Western Wall, Jerusalem, Israel, Middle East

Nyhavn, Copenhagen, Denmark, Scandinavia, Europe

Near Ribiera Grande, Santo Antao, Cape Verde Islands, Africa

Ming Dynasty city wall ruins and the Marriott Hotel, Beijing, China, Asia

Spiss Castle (Spissky hrad), UNESCO World Heritage Site, Slovakia, Europe

Old city walls, Rhodes, Dodecanese, Greek Islands, Greece, Europe

Western Wall (Wailing Wall) with worshipper, Jerusalem, Israel, Middle East

Western Wall (Wailing Wall) with worshipper, Jerusalem, Israel, Middle East

Aerial view of the medieval castle of Vicalvi overlooking the valley with red cross painted on the perimetral wall, at sunset, Vicalvi, Frosinone province, Ciociaria, Latium region, Lazio, Italy, Europe

Sheep fences and rock walls along the Dingle Peninsula, County Kerry, Munster, Republic of Ireland, Europe

Tiled Walls, Painted Ceiling, The Emir's Wives Quarters, Tash Khauli Palace, 1830, Ichon Qala (Itchan Kala), UNESCO World Heritage Site, Khiva, Uzbekistan, Central Asia, Asia

Tower, Outer Wall of Tosh HovIi Palace, Ichon Qala (Itchan Kala), UNESCO World Heritage Site, Khiva, Uzbekistan, Central Asia, Asia

Nagoya Castle, Nagoya, Honshu, Japan, Asia

Mosaics inside the church of Santa Maria in Trastevere, Piazza Santa Maria in Trastevere, Rome, Lazio, Italy, Europe

Yellow flowers and snowy peaks on the roadway to Soglio, Maloja, Bregaglia Valley, Engadine, canton of Graubunden, Switzerland, Europe

A rock climber scales a wall while the sun sets over a mountain in the distance, United States of America, North America

Matthias Church seen from Fisherman's Bastion, Budapest, Hungary, Europe

The Bell Tower at Palamidi Castle, Nafplio, Argolis, The Peloponnese, Greece, Europe

Giglio port, Tuscany, Italy, Europe

The Temple of Athena Nike, Acropolis, UNESCO World Heritage Site, Athens, Attica, Greece, Europe

Waves backlit by the dawn sun reflect off the sea wall and impact with an incoming one, Exmouth, Devon, England, United Kingdom, Europe

Lungarno delle Grazie and Arno river, UNESCO World Heritage Site, Florence, Tuscany, Italy, Europe

Close-up of artwork faces at John Lennon Wall, Prague, Bohemia, Czech Republic (Czechia), Europe

The Ecaterina's Gate (Upper Gate) on the Old City Wall, erected in 1559, Brasov, Transylvania, Romania, Europe

Walls, Assur (Ashur), UNESCO World Heritage Site, Iraq, Middle East

Carpets hanging on a wall for sale in Beysehir, Anatolia, Turkey, Asia Minor, Eurasia

View of ornate wall art just off Friedrichstrasse, Berlin, Germany, Europe

The Jahaz Mahal or Ships Palace in the Royal Enclave, Mandu, Madhya Pradesh, India

Charles Bridge in winter snow, Prague, UNESCO World Heritage Site, Czech Republic, Europe

Tour de Constance (Constance's tower) and city wall, Aigues-Mortes, Bouches-du-Rhone, France, Europe

Visitors and horse carriages beside the outer wall of the Colosseum, Forum area, Rome, Lazio, Italy, Europe

Pied kingfisher (Ceryle rudis), fishing from perch on bridge in Kruger National Park, Mpumalanga, South Africa, Africa

View of Oberbaum Bridge near Eastside section of the former Berlin Wall along the Spree River, Berlin, Germany, Europe