Petrovaradin Fortress clock tower (Novi Sad, Serbia)
Over 300 years ago, the clock tower seen in our June 2019 “mystery photo” was created to be part of the Petrovaradin Fortress in Novi Sad, northern Serbia. On the tower, each of the four clock faces (measuring about 6½ feet in diameter) is unique in that the hour hand is long and the minute hand is short — the opposite of typical clocks. (Being able to see the hour from a distance came in handy for boatmen on the Danube River, which flows alongside the city.)