The poster designs are copyright of bigcityposter.com, map data is fully based on the data by OpenStreetMap®.
For private and non-commercial use only.
OpenStreetMap® is open data, licensed under the Open Data Commons Open Database License (ODbL) by the OpenStreetMap Foundation (OSMF).
The cartography in their map tiles, and their documentation, are licensed under the Creative Commons Attribution-ShareAlike 2.0 license (CC BY-SA).
More information: http://www.openstreetmap.org/copyright