The best alternatives to OpenStreetMap are Open Data Inception, HistoryMaps, and Vacuum Data. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of OpenStreetMap?
Hurreeβ The smarter, simpler way to analyze your data
Open Data Inception is a list of more than 2,700 data portals available around the world. It exists as a map, a list and an API. opendatainception.io is built w/ Bootstrap and open source widgets connecting a source dataset to the map through an API. You can search, filter, and find your local portals in minutes.
ArchaeoXR aims to create fully explorable, intractable and narrative driven reconstructions of archeological sites in VR. We have already created three main worlds (the Athens Agora, the Athens Acropolis and Olympia) on the AltspaceVR social VR platform