"main centers" is a correct and usable phrase in written English
It is often used to refer to the main places of activity or concentration in a particular area, such as major cities or towns. For example, "The main centers of industry in this region are located near the coast."
The main centers of new art in Pakistan are its two largest cities, Karachi and Lahore.
Mitrovica jail, in the Serbian-dominated north of the ethnically divided city, is one of the main centers for Serbian prisoners in the province.
China's main centers for designing, making and storing nuclear arms lie in the shattered earthquake zone, leading Western experts to look for signs of any damage that might allow radioactivity to escape.
Though the road is welcomed by developers, it is bemoaned by transportation advocates who lament that it will lead people to settle far away from the main centers of employment — locking more people into long commutes.
Two main centers of activity were cited: the principal mosque in Foz do Iguaçu and a travel agency there operated by Mr. Abdallah and the man who was then his partner, Farouk Omairi.
Officials said that both Mr. Ahmed and Mr. Payumi attended the mosque in Milan that, after the Sept. 11 terrorist attacks, the United States called one of the main centers of Al Qaeda-sponsored terrorist activity in Western Europe.
In a strange way, his main center is emotion.
The main center for male prisoners was called Libertad-Liberty.
Phil Simms started 106 games with his main center, Bart Oates, for the Giants.
Hours: main center, 8 a.m. to 4 p.m.; the drive is open until sunset.
Once they blockaded Montreal's main center for distributing wine and liquor.
