diff --git a/advent.txt b/advent.txt
index 81558b1..2b063df 100644
--- a/advent.txt
+++ b/advent.txt
@@ -19,12 +19,15 @@ adventure".
 This game is released as open source with the permission and encouragement of
 the authors.
 
-== DISAMBIGUATION ==
 There is an 'adventure' in the BSD games package that is a C
 port of the 1976 ancestor of this game.  To avoid a name collision,
 this game builds as 'advent', reflecting the fact that the PDP-10
 on which it originally ran limited filenames to 6 characters.
 
+== ENVIRONMENT VARIABLES ==
+ADVENTURE::
+   Path to the text database file describing Colossal Cave.
+
 == REPORTING BUGS ==
 Report bugs to Eric S. Raymond <esr@thyrsus.com>.  The project page is
 at http://catb.org/~esr/open-advent