Turkish Holidays and Festivals
Note that this isn't a complete list; holidays strike without warning. On the days preceding national and religious holidays, many people have the afternoon off, if not the entire day. Dates for Muslim holidays are set according to a lunar calendar, so the specific dates vary from year to year. Even though Christian holidays (such as Easter, Ascension, and Christmas) are not celebrated in Istanbul, the city is especially crowded during these times with visiting Europeans.

Jan 1 New Year's Day (Yılbaşı, national holiday)

Late March-mid-April International Film Festival (www.iksv.org/film/english)

March  Easter Week (Christian holiday)

April 23 National Sovereignty and Children's Day (national holiday)

May  Ascension Weekend (Christian holiday)

May 19 Atatürk Commemoration and Youth Day (national holiday)

June International Music Festival (www .iksv.org/muzik/english)

Early July International Jazz Festival (www.iksv .org/caz/english)

Aug 24-27 (in 2007) Turkey Grand Prix (www.turkeygrandprix.com/en)

Aug 30 Victory Day (national holiday)

Sept 8-Oct 4 International Istanbul Biennial (www.iksv.org/bienal/english)

Ramadan Festival (Muslim )

Mid-Oct October Film Week (www.iksv.org)

Oct 29 Republic Day (national holiday)

Dec 20-23 Sacrifice Festival

Kurban Bayrami (Muslim festival)

Dec 24-Jan 1 Christmas Week (Christian holiday)
 

Your Guide to Istanbul.