101st kilometre (Russian: 101-й километр, sto pervyy kilometr) is a colloquial name for the law restricting freedom of movement in the Soviet Union.
In the Soviet Union, the rights of an inmate released from the prison would typically still be restricted for a long period of time. Instead of regular documents, inmates would receive a temporary substitute, a "wolf ticket" (Russian: волчий билет, volchiy bilet), confining them to internal exile without the right to settle closer than 100 km (62 mi) to large urban centres. This has resulted in many residential communities established at 101 km (63 mi) away from city borders. In modern Russia, the restrictions have been abolished and the expression is used in a context similar to that of boondocks.