Debord says in Theory of the Dérive

Debord says in Theory of the Dérive (1956):

One or more persons engaging in dérive give up, for a greater or lesser duration, their familiar reasons for movement and action, their own acquaintances, jobs, and forms of leisure, to release themselves to the solicitations of the site and of the encounters suiting it. The place of the aleatory here is less determinant than is thought: from the point of view of dérive, there is a psychogeographic relief of cities, with constant currents, fixed points, and vortexes that make approaching or exiting certain zones very difficult.

via Psychogeography: where writers should now fear to tread | Aeon Essays