Ħaġar Qim and Mnajdra!!
Malta is so lucky to some of the oldest buildings in the world. Older than Stonehenge and the Pyramids.
Built by Neolithic (New-StoneAge) culture that seemed peaceful. These temples have only been found in Malta and Gozo, even though the temple-builders were surely in contact with Sicily and other Italian islands.
The theory is that Malta & Gozo were "sacred" islands. Places were travellers came from afar to worship. (Malta & Gozo is full of these temples)
Besides the temples there are great scenic views of the Maltese countryside and the sea. This spot is very close to the Blue Grotto, which you can visit by walking there afterwards :)