The image shows the calendar dial of the Prague Astronomical Clock (Staroměstský orloj).
It is the oldest working astronomical clock in the world, installed in 1410.
The clock is located on the south wall of the Old Town Hall in Prague.
The calendar dial, painted by Josef Mánes in 1865, shows the months of the year
and medallions with the signs of the zodiac. It is an important cultural symbol
and a masterpiece of medieval craftsmanship.