The story of this place
The Jesuits arrived in Prague in 1556 and over 170 years assembled the Klementinum, a fortress-sized complex second only to the castle. Its 1722 Baroque Library Hall glows with ceiling frescoes of learning and a gallery of antique celestial globes, so precious it is now viewable only through a rope barrier. The Astronomical Tower let Jesuit scholars track the sun; each day at noon a keeper once waved a flag to signal the exact hour to the city. From this tower, meteorologists have kept a continuous daily weather log since 1775 — one of the longest unbroken climate records in the world. Mozart and the young Kepler both passed through its halls.