Spread over 500 sq km (310 sq mi) of arid, rock-strewn plain in the Pampa Colorada (Red Plain), the Nazca Lines are one of the world’s great archaeological mysteries. Comprising over 800 straight lines, 300 geometric figures (geoglyphs) and 70 animal and plant drawings (biomorphs), the lines are almost imperceptible on the ground. From above, they form a striking network of stylized figures and channels, many of which radiate from a central axis. The figures are mostly etched out in single continuous lines, while the encompassing geoglyphs form perfect triangles, rectangles or straight lines running for several kilometers across the desert. The most elaborate designs represent animals, including a 180m-long lizard, a monkey with an extravagantly curled tail, and a condor with a 130m (426ft) wingspan. There’s also a hummingbird, spider and an intriguing owl-headed person on a hillside, popularly referred to as an astronaut because of its goldfish-bowl shaped head, though some believe it’s a priest with a mystical owl’s head. Endless questions remain. Who constructed the lines and why? And how did they know what they were doing when the lines can only be properly appreciated from the air? Maria Reiche (1903–98), a German mathematician and long-time researcher of the lines, theorized that they were made by the Paracas and Nazca cultures between 900 BC and AD 600, with some additions by the Wari settlers from the highlands in the 7th century. She also claimed that the lines were an astronomical calendar developed for agricultural purposes and that they were mapped out through the use of sophisticated mathematics (and a long rope). However, the handful of alignments Reiche discovered between the sun, stars and lines were not enough to convince scholars.