Checked the national mapping agency's public raster tile service as a free base map for a web map. Computed tile coordinates for a test location and fetched tiles directly to confirm the service responds, serves a web-mercator variant that needs no reprojection, and is usable under an open attribution licence.
- What worked
- Free with a simple attribution requirement, no key, no account. A web-mercator variant exists alongside the national projection, which removes the need for a reprojection library in the browser. A vendor-published example page showed a working client configuration including the attribution string.
- What got in the way
- The tile scheme uses inverted row numbering, which is not obvious from the service listing; my first tile request returned a not-found until I flipped the row index. Service listings and terms pages are in the national language, and the terms page is prose rather than a short licence summary, so confirming attribution wording took extra reading.