I almost forgot to add Lato, a must-see archaeological site near Agios Nikolaos. It was in our view the most impressive site in eastern Crete, even better than Knossos. It is a marvellous location with great views in two directions. There are still some impressive walls of buildings remaining, not reconstructed. centrally there is a vast well and around it remains of public buildings.
Just follow the signs, it is well sign posted. A large car park in front of the gate offers no shade, nor drinks. So don't forget to bring your own. There is a small climb to the site, which can be tricky on the way down!