Veerenni (Veerenn) 
Channel, gutter, conduit, flume, lit. ‘water groove’. The -renn ending comes from German Rinne, channel or gutter, see Pikk. Records of the 4-km canal supplying moats and watermills with water from Ülemiste lake as well as Tiigiveski and Härjapea rivers date back to 1345, so the word could also mean viaduct. A very small part of the (now?) underground system is exhibited outside Süda P. No.2.