Turns out the ACT is one of the most surveyed, scanned and digitised bits of real estate on the planet, and most of it is available under various forms of open license (please make sure you check). Here is a list of some of the more important data sources that have been used in development of namadgi.au:

Geospatial data

• GIS data: All the layers you need to create base maps such as elevation (LiDAR), vegetation, soil, rivers and streams and roads are available from ACTmapi and the ACT Government Geospatial Data Catalogue under open licenses.
• GIS desktop software: QGIS is amazingly good for building maps and the QTiles plugin makes it trivial to generate map tiles.

Map tiles

Still looking for topographic map tiles with adequate zoom range. We need a nested set of tiles that show different levels of detail at different Zoom ranges in order to avoid visual clutter and performance problems:

• Interim map tiles: Open Topo Map generously makes beautiful pre-rendered tiles available under the CC-BY-SA 3.0 license. For the moment, the web map runs on these. We are looking into rendering our own using Open Topo Map data and tools.
• Current fallback option is the generate and style our own map from ACT geospatial data, but this will be a lot of work!
• NSW provides magnificent 1:25000 map files, under a CC-BY-SA 4.0 license, but it's a fixed level of detail. Great for close in views, but problematic at lower zoom.
• Web map: The dynamic pan-and-zoom web map is rendered with the Leaflet Javascript library.

Thanks to Open Topo Map and the ACT and NSW governments for making their mapping data available under open licenses. These are a phenomenal resource.