Photo: GetYourGuideBoard a brightly painted trajinera and drift through the ancient canals of Xochimilco, the last remnant of the lake-city the Aztecs built, past floating gardens, mariachi boats and vendors selling snacks from the water. It is loud, colourful and joyous, especially at weekends. Bring cash for food and music, go with a group if you can, and let the mariachis talk you into a song or two as you glide along the waterways.