The naval base of the Black Plain Army was a strategic place not only because it was the only sea defense of Minos' territory. But also because it carried the valuable resources that made most of the services and projects of that young man's government possible.
Hence, it was in Minos' interest that the second city on the Black Plain would be built in the vicinity of that base.
With this, the new city could have a more convenient cargo port for shipping local resources overseas. At the same time, the naval base could fulfill its intended role of protecting the region's coastline.
On the other hand, by building a city's basic infrastructure in that area, Minos could have more soldiers in that base and provide higher quality services for those staying there during the war.