OpenHistoricalMap has use collaborative mapping
Sister projects
Several open collaborative mapping projects integrate with the OpenStreetMap database or are otherwise affiliated with the OpenStreetMap project:OpenHistoricalMap is a world historical map based on the OpenStreetMap software platform.
OpenRailwayMap is a detailed online map of the world's railway infrastructure, built on OpenStreetMap data. It has been available since mid-2013 at openrailwaymap.org.
OpenSeaMap is a world nautical chart built as a mashup of OpenStreetMap, crowdsourced water depth tracks, and third-party weather and bathymetric data.
Wheelmap.org is a portal for mapping, browsing, and reviewing wheelchair-accessible places.