There exists a peculiar pilgrimage undertaken by serious watch collectors, one that has nothing to do with boutique openings or manufacture tours. It leads instead to a tower erected in 1218—27 years after the founding of Bern in 1191—by Duke Berchtold V of Zähringen. Here, in this structure that predates Swiss watchmaking by centuries, a clock has been marking time since 1530—nearly three centuries before the first Vacheron Constantin left the atelier of Jean-Marc Vacheron.