A living instrument · Prague, Czechia

The clock that
holds the sky.

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Travel through one imagined day at the Orloj—the medieval astronomical clock that still animates Prague’s Old Town Square. Drag the timeline to watch its visible instruments move together.

solar motionlunar motion
THE ORLOJ / 50°05′N · 14°25′E · STAROMĚSTSKÉ NÁMĚSTÍ · STARÉ MĚSTO · PRAHA 1 LIVE STUDY
♎♏♐♑♒♓♈♉♊♋♌♍XIIIIIIIIIVVVIVIIVIIIIXXXIXIIIIIIIIIVVVIVIIVIIIIXXXIORLOJ · PRAGUEEARTH · CENTERJANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC✦TWELVE APOSTLESVANITYDEATHCALENDAR OF THE YEARNIGHT · 00:08
Fixed center · Earth 00:08 Prague local time · CET/CEST New moon · 12% lit
one day · approximate study
14 Oct 2026 · 00:08 Prague time
night watchAutumn · Sun in LibraSun phase · New moon · 12% lit
00 midnight06 sunrise12 noon18 sunset24
Anatomy of an instrument

Everything moves
for a reason.

Read the actual face as a layered instrument: the blue-and-gold dial, moving rings, hands, and the symbolic figures that frame it on the tower, each a meditation on time’s passing.

Prague astronomical clock on the Old Town Hall tower, with its blue and gold astronomical dial and surrounding statuesTHE ORLOJ · OLD TOWN HALL · PRAGUE
01 / 09
A short history
1410Construction begins on the astronomical clock.
c. 1490The first calendar dial is added beneath the astronomical face.
1865–66Reconstruction adds the Apostle figures and Mánes calendar plate.
1945The Old Town Hall is damaged; the clock is restored after the war.