St. Olaf's Church (Oleviste kirik) is one of Tallinn Old Town's most recognizable landmarks, its slender spire rising above the medieval rooftops. First recorded in the 13th century and largely rebuilt in Gothic style in the 15th, the church was named for Norway's King Olaf II. Its spire was once reputed to be among the tallest structures in the world, though its historical height is debated.
The church served Tallinn's medieval merchant community and later became a centre of the Reformation. Lightning strikes and fires repeatedly damaged its tower; the present spire stands around 124 metres high. During the Soviet occupation, the KGB reportedly used it for radio surveillance, adding a more ominous chapter to the building's history.
Inside, the lofty, whitewashed Gothic nave offers a quieter contrast to the busy Old Town streets. The tower is the main attraction for many visitors: a steep, narrow stone staircase leads to an observation platform with sweeping views over red roofs, church spires and Tallinn Bay. The platform generally opens seasonally, so check current hours before visiting. Allow time for the climb, wear comfortable shoes and consider coming on a weekday morning when the church may be quieter.