This paper studies integration of regional goods markets in Russia over 2001-2019, analyzing the law of one price. The analysis involves all pairs of country's regions, which provides a comprehensive spatial pattern of market integration. The region pairs are classified as belonging to one of four groups: integrated, conditionally integrated, not integrated but tending towards integration (converging) and neither integrated nor tending towards integration (among these, diverging). On average, a region is found to be perfectly and conditionally integrated with 48.7% of other regions and tending towards integration with 3.3% of them. Non-integration is due to random walking (41.2%) and deterministic divergence (6.8%). Geographical reasons explain the pattern obtained only partially. Apparently, idiosyncratic features of regional markets play a main role in non-integration.