Crete is a magnificent island, which is rather big as well. So, a few days will not be enough to explore it all. That’s why I will recommend some places you should totally not miss!
Chania is the second largest city in Crete, located on the northwestern part of the island. The old town is full of picturesque alleys which will definitely take you back in an other era. There you will find various shops to buy jewelry, souvenirs, raki(!) and whatever else you are fond of. You will also find restaurants and bars where you can spend your night, such as the awarded "Boheme". Here are a few must-visit places in the city.
Characterized by stunning Renaissance Venetian architecture, Rethymno is the third largest city in Crete. Here's where to go while in Rehtymno.
Heraklion, the fourth biggest city in Greece. It might not be the most beautiful of all, but it certainly has its special places. The lions are the meeting spot in the center of the city. If you arrange a date there, you can enter the alleys around there, where you will find many different cafeterias to enjoy your coffee. Now, if you prefer wandering on foot, you can go on towards the sea and Koule for a walk. If you ever find yourself in Heraklion you should not skip visiting Knossos and the Aquarium.