Hajj refers to your set of prescribed pursuits you'll need to execute with the holy land of Mecca. The Hajj pilgrimage is held within the month of Zulhijjah annually. That is also considered as an annual gathering of world Muslims. هُوَ ٱلَّذِى بَعَثَ فِى ٱلْأُمِّيِّـۧنَ رَسُولًا مِّنْهُمْ يَتْلُوا۟ عَلَيْهِمْ ءَايَـٰتِهِۦ https://islamarticle.com/blogs/benefits-of-sixth-kalima/