st petersburg austria and hungary he has collaborated on many famous archaeological projects such as that of the chiang grave of the first chinese emperor and the graves of sipan in peru his museum in mainz belongs to the most reputable in the world for elite excavations and dr detlef gronenborn is part of the team at the roman germanic central museum in mainz his areas of expertise leading him back and forth across the globe are the neolithic period the iron age and the historical periods of western africa the prehistorian and archaeologist is certainly not in nigeria for the first time twelve ...