It is definitely worth visiting the remarkable Archaeological Museum of Aghios Nikolaos, located near the lake. You will have the chance to admire funerary gifts from Neolithic tombs (3,000 - 2,300 B.C.), many vessels dating back to the Minoan era, findings dating back to the Geometric and Archaic period and, finally, funerary gifts found in Roman tombs.
The Folklore museum houses exhibits associated with the life of the Cretan people in modern times. You will have the chance to observe local costumes, weapons, coins, loom-woven fabrics and embroideries, books, etc.
The Byzantine chapel of Panaghia, located near the Aghia triada cathedral, ant the one dedicated to Aghios Nikolaos (with magnificent frescos dating back to the 14th century) are worth a visit.
You can also visit the church of Aghia Aikaterini, where you will have the chance to admire works of ecclesiastical art as well as rare ecclesiastical relics. Medieval religious icons made by painter Michael Damaskinos, considered real masterpieces, are exhibited here.