Awarded UNESCO World Heritage Site status in 2014, the Qhapaq Ñan is the world’s largest heritage-protected site

The 40,000-kilometre (25,000-mile) Qhapaq Ñan (“Royal Road” in Quechua) has been compared with the Roman road network that criss-crossed Europe and remains the foundation for many modern-day roads. It was, according the Spanish conquistadors in conquered the Incas in 1536, more comprehensive and better engineered than any road network in Europe at that time.

It was designed as a means of transporting goods, soldiers and information, and constructed over a period of just 90 years, the period in the 15th and 16th centuries when Tawantisuyu (the Inca empire) stretched from Colombia in the north to Chile and Argentina in the south. Much of it was based on earlier roads and pathways built by the Wari (northern Peru) and Tiwanaku (Bolivia) peoples. Like the Romans, the Inca favoured the direct route, even in the midst of the Andes, where you’d expect the terrain to repel such an approach. Often laid with stone blocks with the flatter side face up, they climbed the rugged mountain terrain via great staircases that have in many cases have survived into the modern era.

The roads were up to seven metres wide in towns and the most significant fortresses and temples. In more far-flung and vulnerable parts of the empire, every five kilometres there was a relay post (Chasqui Wasi), every eight kilometres a fortress (Pukara), every 20km an inn or resting place (Tambo), with a bigger settlement (Llacta) every 50km – their location can often be identified by place names.

Famously, the Incas didn’t use wheeled transport, although they did use the wheel in other instances, when making children’s toys, for instance. Instead they used pack animals, usually llamas, while information was carried by messengers (Chasquis), who would work in relays and were able to cover 240 kilometres in a day.