The Round Tower

The Round Tower is a thirty-five-meter-tall masonry cylinder characterized by a continuous, hollow core around which a wide, helical ramp winds seven and a half times toward the summit. Commissioned by King Christian the Fourth and completed in sixteen forty-two, this structure was designed as an astronomical observatory for the University of Copenhagen, intended to elevate scientific study above the smoke and street-level activity of the city. It remains the oldest functioning observatory in Europe.