Here we present the abstract of the corresponding publication by researchers Luisa Ferro and Giulio Magli:
Alexander the Great founded Alexandria in 331 BC. An examination of the topography of the city today allows the identification of the essential elements of the original urban system, and shows that the site was chosen mainly for religious and symbolic reasons. In fact, Alexandria was the prototype of a series of Hellenistic towns designed as ‘king’s towns’ that aimed to make explicit the divine power of their founder. We examine the orientation of the orthogonal grid, which was based on a main longitudinal axis, and show that this axis is orientated to the rising sun on the day of Alexander the Great’s birth. At the time of foundation, ‘King’s Star’ Regulus was also rising along the same direction.
(One may find the paper here http://onlinelibrary.wiley.com/wol1/doi/10.1111/j.1468-0092.2012.00394.x/abstract)