This site, about 1km away from Masjid Quba is where the Jewish tribe of Banu Nadhir resided. Despite having a peace treaty, they conspired against the Muslims and even made an attempt on the life of the Prophet (ﷺ). They were expelled from Madinah in 4 AH and fled to Khaiber and Syria.
(more to follow)
References: Wikipedia, History of Madinah Munawwarah – Dr. Muhammad Ilyas Abdul Ghani