OpenTopoMap is a free, topographic map generated from the data in the OpenStreetMap and SRTM elevation data. The tile style is based on the official maps and is based on good readability through high contrast and balanced signatures.
OpenTopoMap is licensed under CC-BY-SA . This means that the tiles may be used free of charge and free of charge, as long as attribution always takes place and the transfer is possible under the same conditions.
Click to download OpenTopoMap.tltx