Huge appartment, furnished and decorated tastefully, very well equipped, in a characterful old building in a street off the north of Rynek Glowny main square, 1 minute walk from the square itself.
Everything you could want is easily at hand, with more bars and restaurants a short walk from the door than you could ever grow tired of, and many of the main sights, and public transport links, comfortably in walking distance.
The only thing stopping me rating this a 5 is difficulty sleeping, due to street noise and early morning sun streaming into the bedroom.
Once we learned to close all windows at night and sleep without bedding, the noise was no longer an issue, and I very much doubt if there is anywhere truly central in Krakow that is quiet - it's just the price you pay, and for us it was worth it.
A pair of blackout eye patches might be a good idea if you stay here, or hopefully the owner might fit heavier curtains, to keep some of the dawn sunlight out. mehr