In an effort to provide a standard methodology for map-making for travellers, Wikitravel has a page called the Mapmaking Expedition. It is a Wikitravel Expedition* written to organize and standardize the maps used in Wikitravel. They have a nice basic symbology page.
*A Wikitravel Expedition is a special sub-project for Wikitravel articles or images. Expeditions help Wikitravellers collaborate and organize around certain subjects, be they based on shared interests, geography, or shared skills.
http://wikitravel.org/en/Wikitravel:Common_map_symbols