Cahokia, near Collinsville, Illinois, was the largest city in pre-Columbian North America, built by the Mississippian culture between 900 and 1200 CE with a central earthen mound larger in base area than the Great Pyramid of Giza. A UNESCO World Heritage Site since 1982, it includes Monks Mound, a reconstructed solar calendar (Woodhenge), and evidence of a complex society with long-distance trade, astronomical knowledge and monumental civic architecture — all created without metal tools or written records.

Monte Albán, perched on an artificially leveled mountaintop 400 metres above the Valley of Oaxaca, was the capital of the Zapotec civilisation from 500 BCE to 700 CE and one of the first cities in the Americas. Its Great Plaza, arrow-shaped Observatory, carved Danzante slabs and over 200 tomb chambers document a culture with writing, advanced astronomy and monumental architecture centuries before the better-known Aztec and Maya reached their peak.

The Gyeongju Historic Areas preserve the capital of the Silla Kingdom across five distinct urban districts including royal burial mounds, an intact astronomical observatory from 632 CE and two of Korea’s finest Buddhist monuments at Bulguksa Temple and Seokguram Grotto. Reachable in two hours from Seoul by high-speed train, Gyeongju offers one of the most concentrated and varied UNESCO heritage experiences in East Asia.

Leptis Magna, UNESCO-inscribed in 1982, is one of the Roman world’s best-preserved cities — the birthplace of Emperor Septimius Severus, who transformed it with the Severan Forum, the great Basilica, and a monumental triumphal arch. Buried under Saharan sand for centuries, its theatres, baths and colonnaded streets survive in extraordinary condition, though Libya’s political situation currently limits access.

Robben Island (UNESCO 1999), located seven kilometres from Cape Town in Table Bay, held Nelson Mandela for 18 of his 27 prison years and hundreds of other anti-apartheid activists in its maximum-security political prison from 1961 to 1991. The site’s guided tours are led by former political prisoners, and the island’s earlier history as a leper colony and colonial place of banishment extends its significance across four centuries. Ferries depart from the V&A Waterfront and advance booking is essential.

The Ruins of Kilwa Kisiwani (UNESCO 1981, on the Danger list since 2004) preserve the coral-stone remains of the most important medieval Swahili trading city in sub-Saharan Africa, including the oldest standing mosque south of the Sahara (founded c. 800-900 CE) and Husuni Kubwa Palace (c. 1320-1333 CE) — the largest pre-colonial building in the region. The island, reachable only by dhow from Kilwa Masoko in southern Tanzania, controlled the East African gold trade connecting the Zimbabwe Plateau to Arabia, India and China for six centuries.

The Royal Palaces of Abomey (UNESCO 1985) preserve the 44-hectare earthen palace complex of the Kingdom of Dahomey in Benin, built by 12 successive kings from c. 1625 to 1900 CE. The site is notable for its bas-relief visual history panels, the legacy of the Agojie female military corps, and the 2021 return from France of 26 royal treasures looted during the French conquest of 1892. Abomey lies 145 kilometres north of Cotonou and is best reached by road.

The Archaeological Site of Carthage, inscribed by UNESCO in 1979, preserves two superimposed cities 15 kilometres northeast of Tunis: the Phoenician trading metropolis founded around 814 BCE that dominated the western Mediterranean, and the Roman Carthago rebuilt from 29 BCE that became one of the largest cities in the Roman Empire. Key monuments include the Baths of Antoninus — the third largest Roman baths in the ancient world — and the Punic Tophet sanctuary containing over 20,000 funerary urns. The site is accessible by suburban railway from central Tunis.

The amphitheatre of El Jem (UNESCO 1979) in Thysdrus, built c. 230–238 CE, is the third-largest Roman amphitheatre in the world with a capacity of 35,000, built entirely of dry-laid limestone without mortar. The wealth of Thysdrus derived from olive oil exports across the empire; in 238 CE the governor Gordian I was proclaimed emperor here in a reign lasting 36 days. The adjacent Archaeological Museum holds the finest Roman mosaic collection in Tunisia.

Timgad (UNESCO 1982) — Colonia Marciana Traiana Thamugadi, founded by Emperor Trajan in 100 CE for veterans of the Third Augustan Legion — is the finest surviving example of Roman orthogonal urban planning, preserved by Saharan sand burial from the 7th century until French excavations from 1881. The site on the Algerian steppe at 1,050m includes a triumphal arch, a 3,500-seat theatre, 14 bath complexes, a public library, and complete street grid legible in both plan and pavement.