Tunnel in the Sky | Robert A. Heinlein
A group of students goes through the gate to an unknown planet for a two-to-ten-day final exam in Advanced Survival only to realize, after a period of fighting the elements and wildlife, that something has gone wrong with the gate and what was a brief survival exam has become an endless struggle for life. Reprint. 10,000 first prinitng.
Tunnel in the Sky |