According to Billroth, "What has given me the most joy in my life is the establishment of a school that carries on my aspirations and aims, be it scientific or humanitarian thereby ensuring a legacy for the future."11 Indeed, the school of Billroth was the most lasting and influential school in most of Europe. Its representatives headed surgical clinics in Lüttich, Belgium (Karl Gussenbauer, Alexander Winiwarter), Utrecht, the Netherlands (Friedrich Salzer, Albert Narath, Anton von Eiselsberg), Freiburg, Germany (Vincenz Czerny), Heidelberg, Germany (Czerny, Narath), Königsberg, Prussia (Eiselsberg), Krakau (Johann von Mikulicz [1850-1905], who developed esophagoscopy and gastroscopy), Prague (Gussenbauer, Anton Wölfler, Hermann Schloffer, Karl Maydl), Innsbruck (Viktor Hacker, Schloffer), and Graz (Wölfler, Hacker).