During Ramadan, observant Muslims fast between dawn and sunset. This is not an ideal time for visitors as many shops, businesses, and restaurants are closed (or have limited hours) and public transportation may be less frequent. Since the holiday follows the Muslim lunar calendar as opposed to the western Gregorian calendar, exact dates vary from year to year – in 2008 the holiday occurs throughout the month of September; in 2009 it takes place from August 21st to September 19th.