[tetris11]

Turkey has bad city names even in its own language.

Along the north coast, you will find a town called Çarşamba (Wednesday), which if you continue to drive for a few hours is followed by a town called Perşembe (Thursday).

[skrebbel]

The name of the capital of Tajikistan, Dushanbe, means Monday as well iirc.

[dullgiulio]

Most probably all these names just indicate market day...

[HorkHunter]

Sounds plausible,

Similar to weekday names in Portuguese.