Kyustendil is a town in the far west of Bulgaria, the capital of the Kyustendil Province, a former bishopric and present Latin Catholic titular see.
The town is situated in the southern part of the Kyustendil Valley, near the borders of Serbia and North Macedonia; 90 km southwest of Sofia, 130 km northeast of Skopje and 243 km north of Thessaloniki. The population is 37 799, with a Bulgarian majority and a Roma minority. During the Iron Age, a Thracian settlement was located within the town, later known as Roman in the 1st century AD. In the Middle Ages, the town switched hands between the Byzantine Empire, Bulgaria and Serbia, prior to Ottoman annexation in 1395. After centuries of Ottoman rule, the town became part of an independent Bulgarian state in 1878.
Wikipedia https://en.wikipedia.org/wiki/Kyustendil
Coordinates 42°16'51.584" N 22°41'20.471" E