Deyr-e Gachin is a caravanserai on the edge of the desert south-east of Tehran, a fortified rest house of mud brick and stone, built to shelter merchants and their animals on a long road across the dry plain. Such buildings were the motels of old Persia, set a day's march apart along the trade routes, with a gate wide enough for loaded camels, a courtyard for the animals and rooms for the travellers around it. This one stands in a wide flat landscape of salt flats, gravel and low hills, and the light is bright and hard.
What is clear is that it belongs to a long tradition of roads and trade, which linked the cities of the Iranian plateau with the markets of Mesopotamia, India and Central Asia. The Silk Road was not one road, but many, and caravanserais like this one were the places where goods and news changed hands.
The nearest town is Eqbalieh, about twenty-nine kilometres away, with some 37,000 people, and it has fuel and shops. The road there crosses a dry, open plain, with the great salt desert, the Dasht-e Kavir, not far to the east, and wind can raise dust. Fuel stations are fewer than in the settled north, so keep the tank full. The ride continues to Tehran, where the Golestan Palace, a jewel of tilework and mirrors from the Qajar period, is a UNESCO World Heritage site and a world away from this silent stone yard.
Spring and autumn are the best times, when the days are warm and the nights cool. Summer heat is fierce, and shade is scarce. Bring plenty of water, and wear a scarf against dust. Standing in the old courtyard at dusk, with the walls glowing and the desert silent, it is easy to imagine the camel bells and the smoke of cooking fires.