1. Which river passes by Sofia?
A. The Iskar
B. The Danube
C. The Maritsa
2. Which Bulgarian tradition takes place on the morning of 1 July?
A. Slaughtering of home-bred pigs
B. Greeting the rising sun
C. Dancing barefoot in live coal
3. Which was the last project of Bulgaria-born artist Christo?
A. The Floating Piers