diff --git a/README.md b/README.md
index 6c70dbe..ca1419c 100644
--- a/README.md
+++ b/README.md
@@ -12,7 +12,23 @@ For a quick test run, point the script at the cache.example directory:
 ./generate_map.py --cache-directory cache.example
 ```
 
+Find the result in the files `map.svg` and `map.png`.
+
+If the wrong font is used in the PNG, make sure the chosen font is installed on your system. ([CairoSVG](https://cairosvg.org/) does not support the use of `@font-face` in style sheets.)
+
+When not cache exists or forcing cache renewal, you need to provide the HTTP Basic Auth credentials to doku.ccc.de via an environment variable:
+
+```
+export DOKU_CCC_DE_BASICAUTH=username:password
+```
+
+A run without cache takes some time as it fetches all data from their sources:
+
+1. Get a list of countries in Europe and federal states in Germany from [Wikidata](https://wikidata.org).
+1. Download all these countries' and states' border shapes from Wikimedia Commons.
+1. Get a list of Erfas & Chaostreffs from the doku.ccc.de Semantic Mediawiki API.
+1. Resolve all POIs' (Erfas & Chaostreffs) street addresses' to geocoordinates using [Nominatim](https://nominatim.org/).
 
 ## Fonts
 
-The font contained in `style/concertone-regular.ttf` was created by Johan Kallas (johankallas@gmail.com) and is licensed unter the terms of the SIL Open Font License v1.10.
\ No newline at end of file
+The font contained in `style/concertone-regular.ttf` was created by Johan Kallas (johankallas@gmail.com) and is licensed unter the terms of the SIL Open Font License v1.10.