Lodz and Warsaw are very close together. Lody alos has a huge population one of the biggest cities in Europe but I am surprised that a 737 can operate there as it only has a tiny runway.
I’ve been doing a little research into Lodz (pronounced “wootch” apparently!) and Shamrock seems to be correct as it has a population of 1 million people and is about 80 miles southwest of Warsaw. Not really close enough (in my opinion) to feasibly make it a Warsaw Airport. I’d rather use Wizz or easyJet who fly to Warsaw proper.