The tulou of southwestern Fujian look like something dropped from the sky, huge round or square earthen fortresses sitting among tea terraces and bamboo, with roofs that curve like turned-up eaves. Tianloukeng is a cluster of them in Nanjing County, in the hills inland from Xiamen, and the group is probably the most photographed in the region because it can be seen as a whole: a square tulou at the centre, surrounded by round ones, set on a slope so the roofs stagger like a bowl of dumplings.
They were built by Hakka communities, who migrated south from the Chinese heartland over centuries and often found themselves unwelcome neighbours. The answer was architecture. A tulou has walls of rammed earth, sometimes more than a metre thick at the base, and a single heavy gate, so a whole clan could shut themselves in during a feud or a bandit raid. Inside, families lived in rooms on several storeys around a shared courtyard with a well and an ancestral hall. Some held hundreds of people. The Fujian Tulou were inscribed by UNESCO in 2008, and the Tianloukeng group was part of that listing.
Nothing about the surroundings is flat. The roads wind up through narrow green valleys, tight and steep, with villages along the way and old men selling tea at the roadside. Expect narrow lanes, delivery trucks and the occasional water buffalo, and wet roads in the damp season. Fog is common in the hills, and spring brings rain. Autumn is generally clearer. Note that motorcycles are subject to strict local rules in China, and foreigners usually cannot ride without a Chinese licence and registration, so check what applies to you before you plan to ride here.
There is no sizeable town right at the cluster, so plan to buy fuel and food at a county town on the way in. Local food is built around the hills: mushrooms, bamboo shoots, tea, and Hakka dishes such as braised pork and salted chicken. Many tulou still house residents, and some sell tea in the courtyard. Be a considerate guest, because this is a place where people live, not a museum with its own staff.