A More Accessible Map
http://www.alistapart.com/articles/cssmaps

Duffey, Seth
List Apart, A
2006

Abstract:

Most online mapping applications do not address issues of web accessibility. For a visually impaired web user, these highly visual maps are essentially useless. Is there a way to display text-based data on a map, keeping it accessible, useful and visually attractive? Yes: using an accessible CSS-based map in which the underlying map data is separated from the visual layout.