Ever since humans first began to count, people have clocked days, moons and years, tried to make sense of them in terms of each other, and formed calendars to order their lives. In an amazing leap, the ancient Maya managed to synchronize all the visible planets too. In this tiny guide to ancient calendars, Geoff Stray explains the difference between lunar and solar calendars, the importance of precession, and reveals for the very first time the secret of the Long Count. WOODEN BOOKS are small but packed with information. Fascinating FINANCIAL TIMES. Beautiful LONDON REVIEW OF BOOKS. Rich and Artful THE LANCET. Genuinely mind-expanding FORTEAN TIMES. Excellent NEW SCIENTIST. Stunning NEW YORK TIMES. Small books, big ideas.