Before going to enlist the important cities of the Ottoman Empire it is important to understand why those cities were captured or built by the Ottoman. Also, after the vast regions that came under the Ottoman control, it became only important for the Sultans and administrators to built parallel cities to facilitate trade and eventually expansion.
Cities - throughout history have enjoyed the most attention; they set precedents of art and architecture and the base for a grand civilization to start. They were carefully built and constructed as per the whims and fancies of the regional rulers to become most important examples of their work in the area. Some are as ancient as history itself and some are relatively new; but the striking similarity is that they have preserved their history and heritage till date as they continue their progressive journeys into new millennia.
To start with, Constantinople was the most important city of the Turkish Empire what is known as modern day Istanbul. It was the reigning capital of 4 Empires including the Ottoman Empire and therefore it ought to be the capital of the Empire.
The city held out a lot for the Turks to learn as it had influences from its past Empires and rulers that ruled over it. It had emerged as the biggest and most important urban center in the whole of Europe. It held the distinction of being the wealthiest city too, not just in Europe but throughout the world for a brief period of time. Other important cities are:
6. Stamboul (not to be confused with Istanbul)
7. Kars in Modern day Turkey
8. Tabuk in Saudi Arabia
All these cities were the biggest urban conglomerates in the European region and were also important military command centers and facilitated trade throughout western Asia and Eastern Europe. They also held large sways of power throughout Europe as then; the Ottoman Empire was a force to reckon with.
If one considered the geographical location of these cities; the common pattern that would arise is that all of them fall on major trade routes and therefore that was the main reason of their springing up at places scattered evenly throughout the Empire. Good administration oversaw the law and order of the regions along with the business requirements of the regions. Satellite townships were an opposed to idea back then.