Before flowing into the Black Sea at the end of its 2 850km journey, the Danube opens out into Europe’s largest and best-preserved delta, composed of three main branches, explored by rowing boat (lotca) from Tulcea: to the north lies Chilia, the longest, giving access to the Letea forest; in the middle is Sulina, the busiest, with the delta’s only town; and to the south is Sfântu Gheorghe, the oldest. With 35 ecosystems comprising thousands of species, the delta is a Unesco protected area.