The far side of the moon is a strange and wild region, quite different from the familiar and mostly smooth face we see nightly from our planet. In 1959 the Soviet Luna 3 space probe took the first photographs of this hidden region. Instead of wide plains, the images showed a moonscape spiked with mountains. Observations since then have shown that the far side is also full of rugged craters, and within them there are yet more craters. Soon this rough terrain and the space just above it will have even stranger features: it will be teeming with radio telescopes, deployed by a new generation of robotic rovers and lunar orbiters.