Almost 300 lighthouses in more than 40 countries and territories -- from Argentina to Wales -- will be on the air for 2010 International Lighthouse/Lightship Weekend (ILLW), organized by Scotland’s Ayr Amateur Radio Group (AARG). The event, held for the 12th year in a row, takes place Saturday, August 21 0001 UTC through Sunday, August 22 2359 UTC. While not a contest, the ILLW is more of a QSO Party and Amateur Radio demonstration.