Well, tomorrow is Halloween, a holiday that has come into our modern life via various cultural and religious festivals. In the Celtic world, Samhain was one of the major holy days celebrated during the year, marking the end of summer and the beginning of winter. In Wales this night was called Nos Galan Gaeaf. It was believed that the dead would walk the earth on this night, and people would build large bonfires to ward them off. As illustrated here by Jonas Lindbärg, people would leap over the flames for luck.