AFAQ Encyclopedia Article
"Burhan-ul-Haq Abu Rehan Al-Beruni, the great and outstanding Astronomer, Mathematician, Geographer and Historian was born at Kath in Khawarzam, Central Asia, on September 4, 973.
His birth took place in the outskirts of Kath, that is why he was called Al-Beruni (outsider). Kath which was ruled by Abu Abdullah Muhammad Khawarzam Shah. The city of Kath was located in the northeast of present-day Urgench (Jurjaniya in Arabic) at the right bank of the river Amu. Kath has been buried under the annals of history, but a town named Beruni keeps the memory of Al-Beruni alive."