Was the city of Constantinople named after the greek city Byzantium? Or was it just built on that former site with a new name?

The city of New Rome was built upon the old site of Byzantium. When Constantine died, the city was renamed Constantinople. The name was changed to Istanbul in the 20th century.

http://www.ancient.eu.com/Byzantium/

Thank you MS. Sue. There were 4 answers with 1 being incorrect and the other 3 checked out correct but I wasn't 100% sure of this one

Yes, the city of Constantinople was indeed named after the Greek city of Byzantium. In the year 330 CE, Emperor Constantine I decided to establish a new capital for the Roman Empire in the eastern part, and he chose the ancient Greek city of Byzantium as the location. However, Constantine renamed the city Constantinople after himself, and it became the new capital of the Eastern Roman Empire (which later became known as the Byzantine Empire). So, to answer your question, it was both built on the former site of Byzantium and given a new name.