Bulgarian workers and archaeologist s research an ancient Roman amphitheatre, found a few days earlier in downtown Sofia during construction work, April 30, 2004. The amphitheatre, which is assumed to date back late 2nd century A.D. or early 3rd century A.D, is some 100m in diameter and was probably used for gladiator fights. Sofia is the third capital in Europe, after Rome and Madrid, where a Roman amphitheatre has been found. REUTERS/Stoyan Nenov SN/AA