St. Catherine's Passage (Katariina käik) is a narrow medieval alley running between Vene and Müürivahe streets, passing along the wall of the former Dominican monastery of St. Catherine. The alley is lined with the tombstones of medieval monks embedded in the monastery wall, and the ground-floor premises have been converted into small artisan workshops — glassblowers, jewellers, textile artists, and ceramicists who work in open studios and sell from their own spaces.
It is one of the most atmospheric corners of the Old Town, easy to miss but well worth finding. The monastery ruins behind the alley can be explored through the adjacent Dominicans' Monastery Museum (Dominikaani kloostri muuseum), which preserves the cloister and holds medieval stonework and artifacts.