Further Rumelia, northeast of Filibe

Densely populated Bulgaria ...

Filibe, in the bottom left corner, is modern-day Plovdiv.  "Filibe" is the Turkish name; prior to the Ottomans taking the city in 1363-4, it was known by the Byzantine name Philippolis, the name it had going back to its founding by Alexander the Great's father, Philip II.  It's an old city, a large city, with a high infrastructure, even though it's virtually unheard of outside Europe.