Round Tower
Seventeenth-century observatory tower climbed by a spiral ramp to a rooftop view of the old city.
Rundetaarn was raised between 1637 and 1642 on the orders of Christian IV as the observatory of the Trinitatis Complex, which also united a university church and a library loft under one roof. It is the oldest working observatory in Europe. Instead of stairs, a helical ramp of some 209 metres winds seven and a half times around a hollow core, wide enough for a horse and cart to carry instruments and books to the top; a rebus in gilded letters above the entrance sets out the king's motto.
The tower stands about 34.8 metres high, and the viewing platform, reached through a wrought-iron screen made in 1643, looks out over the roofs of the medieval quarter. The former Library Hall above the church now serves as a gallery for changing exhibitions and concerts, and the Bell Loft above it holds the church bells. Tsar Peter the Great is said to have ridden up the ramp in 1716. The observatory is still used for public stargazing in the winter months.
Highlights
- 209-metre spiral ramp winding around a hollow core
- Rooftop platform over the old city with a 1643 iron screen
- Library Hall used for exhibitions and concerts
- Working observatory open for winter stargazing
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