Zytglogge: Bern's Medieval Clock Tower & Hourly Show

A 16th-century blacksmith with no clockmaking experience forged a mechanism so durable it still dictates the rhythm of Bern today. Standing at the intersection of Marktgasse and Kramgasse, the Zytglogge is a 54-meter medieval clock tower that marks the boundary where Bern's earliest core transitions into its medieval western expansions. Positioned on the central pedestrian artery, it serves as the defining historic landmark at the center of the UNESCO Old Town.

A Masterpiece of Medieval Engineering

The heart of the Zytglogge is its fully mechanical movement, constructed between 1527 and 1530. When the tower's previous clock failed, the Bern City Council commissioned Kaspar Brunner to reconstruct the massive iron mechanism. Surprisingly, Brunner lacked formal training in horology; he was a master blacksmith and locksmith. Despite this, he engineered one of the most complex and durable late-medieval mechanical movements in Europe.

Today, the clock is still powered entirely by Brunner's 1530 mechanism. It operates through daily manual winding by an assigned clockmaster, who hoists heavy stone weights up through the tower. Later additions to the movement include a pendulum installed by Pierre Angely in 1686, which uniquely utilizes a cannonball as its bob. Inside the stone chamber, the mechanism produces a continuous, audible ticking and gear-clacking.

The Hourly Automaton Show

Approximately four minutes before every full hour, an automated mechanical sequence begins to play for the crowds below. The performance starts with a gilded automaton rooster that flaps its wings and crows, driven by miniature bellows. A seated jester then rings bells and kicks his feet, followed by a carousel procession of armed bears—the heraldic symbol of Bern—marching around the base.

Above them, a figure representing Chronos, the god of time, turns his hourglass and opens his mouth in synchrony with the bell strikes while a nearby lion nods. The sequence culminates when a life-sized gilded figure known as Hans von Thann strikes the 1.4-ton bronze hour bell. Cast in 1405, the deep, resonant strikes of this massive bell reverberate across the arcaded street canyon.

From Defensive Gate to Timekeeper

The Zytglogge was initially built for a vastly different purpose. Constructed circa 1218 to 1220 under the House of Zähringen, the structure served as a western defensive gate and watchpost. As Bern expanded westward, the tower lost its outer defensive role and was temporarily repurposed as a civic prison.

Following the Great Fire of 1405, the stone building was converted into a municipal clock and watchtower to detect fires and standardize civic timekeeping. Its current late-Baroque exterior facade took shape across subsequent renovations in the 17th and 18th centuries. The tower now operates as a historic monument, offering guided interior tours where visitors can climb 130 steps to observe the interlocking gears and automaton levers in action.

Hidden Astronomical Details

The eastern facade of the Zytglogge features an intricate astrolabe dial. This face functions as a 24-hour clock while also tracking zodiac signs, lunar phases, and the Julian calendar. The main exterior dial holds a single hour hand tipped with a golden sun shaped like a 'Schwurhand' (a swear-hand symbol), indicating Bern's historic status as a free imperial city.

Because the 16th-century calendar mechanism does not account for leap days, it requires human intervention to remain accurate. The date hand on the Julian calendar dial must be manually reset by hand once every four years on February 29.