irty-five hundred had their permanent residence in East Berlin. Only about half that number, however, were caught there when the barrier went up.) Word of the planned underground railroad got around quickly, and some fifty other students—Americans, Dutch, British, and Scandinavians among them—joined up. They called their operation Das Reisebüro (the travel bureau), and referred to one another, in the underground tradition, by fictitious names. Though most of the Bureau’s undertakings have been kept secret, a few of its agents, including one known as Der Lange Heinrich (Big Henry), who is a husky, six-foot-two engineering student from Munich, told me something about their methods. In the beginning, the operation was conducted mainly with the use of borrowed passports. A West German student would make a trip into East Berlin, get in touch with one of the trapped students, and return with his photograph. The Bureau would then hunt around for a West German student bearing a passable resemblance to the one in the photograph. If such a look-alike was found, he was asked to assist in the enterprise. Requests for such assistance were seldom refused. The double’s task consisted of making one trip into East Berlin, to secure an entry permit; this was issued at a border checkpoint and was good only on the day of its issuance and only with the passport presented. Having secured the permit, the look-alike would make a quick round trip, and, back in West Berlin, would turn his passport and the entry permit over to the Bureau. Another of its operatives, also able to cross the border legally, would then deliver these documents to the waiting East Berlin student, who would use the borrowed passport and permit to cross the border. When a satisfactory look-alike could not be found, the Bureau took a West German student’s passport, removed the photograph, and substituted a passport photograph, taken in East Berlin, of the student to be brought out. The necessary stamps on the passport were forged by an art student (code name: Herr Rembrandt), who used only sharpened wooden kitchen matches and marking ink to ply his special trade. This system worked well for nearly four weeks, and scores of East Berlin students arrived in West Berlin, courtesy of Das Reisebüro.
In the second week of September, the East Germans changed the procedure at the border. West Germans who had gone into East Berlin were now required to turn in their entry permits at the checkpoint on leaving. To counter this difficulty, Herr Rembrandt quickly turned out a supply of forged permits. But within a week the border authorities created a further difficulty by changing the color, numbering, and stamping of the permits every day. The Bureau then turned to the use of foreign passports, since persons with such passports, unlike those with West German passports, were not obliged to secure entry permits. Foreign passports were in sufficient supply, too, since the Free University alone had some seven hundred foreign students. However, the problems encountered in disguising East Berlin students in alien dress, language, and habits convincingly enough to fool the border guards turned out to be excessive. Though a few successful crossings were made with foreign passports, there were many more failures and consequent arrests. The whole scheme was abandoned when, some weeks later, the East Germans began requiring any person travelling on a foreign passport to apply for a permit to enter East Berlin.
The Bureau, however, keeping a little ahead of the times, had meanwhile been exploring a new escape route—through Berlin’s sewer system. After studying street maps and charts of the intricate network of sewer pipes crisscrossing the city, the Bureau’s operatives laid out possible routes under the wall, and then, at night, went below to test them. The initial aim of the Bureau’s sewer experts was to find the shortest possible route—that is, a route whose East Berlin entrance was situated as near as possible to the wall. Later, they worked out longer routes. Some of the channels were so small 