These minor Islamic festivals are not public holidays, and they won't affect your travel plans much except to make your time in Turkey more interesting and enjoyable.
Note the dates so you can explore—and perhaps participate in—the meaning and delights of the festivals, and remember that these Islamic festivals begin in the evening and last until the next evening:
Regaip Kandili: Prophet Muhammed's conception
Miraç Kandili: Prophet Muhammed's ascent to heaven
Berat Kandili: Day of Forgiveness
Aşure Günü: Martyrdom of Imam Hüseyin
Mevlid-i Nebi: Birthday of the Prophet Muhammed
Regaip Kandili (reh-gah-YEEP kahn-dee-lee), the "Beginning of the Three Moons," first Thursday in the month of Recep (Rajab), celebrating the night of Muhammed's conception, is estimated to fall on:
2018: 21/22 March (Wednesday/Thursday)
2019: 6/7 March (Wednesday/Thursday)
2020: 26/27 February (Wednesday/Thursday)
2021: 17/18 February (Wednesday/Thursday)
2022: 2/3 February (Wednesday/Thursday)
Celebrations include mosque illuminations (pretty and photogenic).
Miraç Kandili (mee-RATCH kahn-dee-lee, Lailat al-Miraj), 27th of Recep (Rajab), celebrates the Prophet Muhammed's ascent into heaven. It's estimated to fall on:
2018: 12/13 April (Thursday/Friday)
2019: 1/2 April (Monday/Tuesday)
2020: 20/21 March (Friday/Saturday)
2021: 9/10 March (Tuesday/Wednesday)
2022: 26/27 February (Friday/Saturday)
Berat Kandili (beh-RAHT kahn-dee-lee, Lailat al-Bara'a), the "Day of Forgiveness," (14th of Şaban) is celebrated on:
2018: 29/30 April (Sunday/Monday)
2019: 18/19 April (Thursday/Friday)
2020: 7 April (Tuesday)
2021: 27 March (Saturday)
2022: 17 March (Thursday)
...lighting up the mosques.
Aşure Günü (AH-shoo-REH gew-new, Ashura), the 10th day of the Islamic lunar month of Muharrem, is estimated to fall on:
2018: 19/20 September (Wednesday/Thursday)
2019: 8/9 September (Sunday/Monday)
2020: 28/29 August (Friday/Saturday)
2021: 18 August (Wednesday)
2022: 8 August (Monday)
It's not a public holiday, but is commemorated in Turkey as the date that: Adam repented his sin, the Prophet Abrahamwas born, Jonah emerged from the whale, and Noah's ark rested on dry land. For Shi'a Muslims, it has extraordinary importance as the day that Imam Hüseyin, the grandson of the Prophet, was martyred on the battlefield of Kerbela (Karbala) in 680 CE/AD.
It will also reputedly be the Day of Judgement—when that comes!
Turks commemorate it by serving a special sweet pudding called aşure (AH-shoo-REH) made with cereals, raisins and nuts.
MEVLİD-İ NEBİ (Mevlid Kandili)
Mevlid-i Nebi (mehv-LEED ee NEH-bee, Mawlid al-Nabi), the Prophet Muhammad's birthday, is fixed as the 12th day of the 3rd month (Rebi' ul-Evvel/Rabi' ul-Awwal) of the Hijri calendar. It's celebrated with mosque illuminations and special foods, and is estimated to fall on:
2018: 18/19 November (Sunday/Monday)
2019: 7/8 November (Thursday-Friday)
2020: 27/28 October (Tuesday-Wednesday)
2021: 17 October (Sunday)
2022: 7 October (Friday)
—by Tom Brosnahan