Well, the Hijri date 11 Ramadan 1420 corresponds to the Gregorian date Sunday, 19 December 1999. This date lies in the ninth month of the Hijri year 1420 AH, which is Ramadan of 1420 AH. Both this Hijri and Gregorian date occur on the single day that is Sunday without any doubt. The Arabic date 1420/09/11 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 19 December 1999 to its equivalent Arabic date.
The following is the conversion of the Arabic date 11 Ramadan 1420 AH to its equivalent Gregorian date.
أَلَمْ تَرَ كَيْفَ فَعَلَ رَبُّكَ بِعَادٍ
Dost thou not consider how thy Lord dealt with (the tribe of) A'ad,
Surah Al-Fajr(89:6)
Sahih al-Bukhari
Holding Fast to the Qur'an and Sunnah
Chapter: The religious learned men should not differ
Narrated Anas:
The Prophet (ﷺ) brought the Ansar and the Quarish people into alliance in my house at Medina, and he invoked Allah for one month against the tribe of Bani Sulaim in (the last rak`a of each compulsory) prayer.
Sahih al-Bukhari 7340, 7341
