Boat travel is a favored way to get around Lake Atitlan. Check out the steep, landslide-prone hills & volcanoes surrounding the lake and you will know why. Some sections of lakeshore have no roads. Boat travel covers more now -- the lake level has risen 3 meters in less than a decade. Cargo travels by boat too.
Tuk-tuks have also increased mightily in the past decade, from zero to loud.
Horses are still in use, for ordinary transport and to power romantic carriages.
Pick-up trucks full of people ply the roads along with colorful busses.