Thanks to Charles for alerting me to this.
Roadside Picnic is a science fiction short novel written in 1971 by Arkady and Boris Strugatsky, published in 1972 and since deemed a classic. The film Stalker directed by Andrei Tarkovsky is loosely based on the novel. The authors later wrote the novel Stalker, in turn loosely based on the film.
Aliens have visited the Earth, and departed, leaving behind a number of artifacts of their incomprehensibly advanced technology. The places where such artifacts were left behind are areas of great danger, known as "Zones." The Zones are laid out in a pattern which suggests that they resulted from the impact of an influence from space which struck repeatedly from the same direction, striking different places as the Earth rotated on its axis.
A frontier culture arises along the margins of these Zones, peopled by "stalkers" who risk their lives in illegal expeditions to recover these artifacts, which do not obey known physical laws. The most sought one, the "golden sphere", is rumored to have the power to fulfill the deepest human wishes.
The name of the novel derives from a metaphor proposed by the character Dr. Valentin Pilman, who compares the visit to a roadside picnic. After the picnickers depart, nervous animals venture forth from the adjacent forest and discover the picnic garbage: spilled motor oil, faded unknown flowers, a box of matches, a clockwork teddy bear, balloons, candy wrappers, etc. He concludes that humankind finds itself in a situation similar to that of the curious forest animals.
WIKI Entry
Amazon Entry