People have been living in cave houses (窑洞; yáodòng) in Shānxī for almost 5000 years; it’s believed that at one stage a quarter of the population lived underground. Shānxī’s countryside is still littered with yáodòng, especially around the Yellow River area, and Lǐjiā Shān is a wonderful example. These days most lie empty and abandoned, but almost three million people in Shānxī (and around 30 million in total in China) still live in caves. And who can blame them? Compared to modern houses, they’re cheap, far better insulated against freezing winters and scorching summers, more soundproof, and they afford better protection from natural disasters such as earthquakes or forest fires. Furthermore, with far fewer building materials needed to construct them, they’re a lot more environmentally friendly. So why isn’t everyone living in them? Well, although most are now connected to the national grid, the vast majority of cave communities have no running water or sewerage system, turning simple daily tasks such as washing or going to the toilet into a mission. Suddenly, even the ugliest tower block seems attractive.