Misaligned map data received from different sources is corrected to generate a map that includes aligned features. Each data source is associated with a reliability value that identifies the likelihood that the map data received from the corresponding source is aligned with a particular map location. A corrected version of the map data is generated based on the reliability values of the data sources. Generally, map data from unreliable sources is adjusted toward map data from more reliable sources until the map data from the different sources is aligned.