Gateway

The Heechee left the solar system long before humanity climbed out of the mud, and all they left behind was Gateway: a hollowed asteroid holding nearly a thousand functioning starships that nobody understands. The controls can be set, but not read. A prospector climbs aboard, launches, and either returns rich beyond calculation, returns with nothing, or does not return at all. Robinette Broadhead wins a lottery in the food mines and buys a ticket to Gateway, and there discovers that the hardest part is not the danger but the decision to face it: the endless waiting, the drinking, the love affairs conducted by people who may be dead next month. Interleaved with the story of his voyages is his later life, comfortable, wealthy and unbearable, spent in sessions with a computer psychiatrist he mocks and cannot leave, circling the thing he did out there and will not say. Pohl's construction is unshowy and merciless, cutting between the two timelines until the reader understands what kind of survivor is telling this story, and what surviving cost the people who were with him.