Rising from the base of Mt. Etna, the largest volcano in Europe, Catania is a town built on ashes. Since its founding in the 8th century BC, a number of massive earthquakes have rocked the city, leaving literal layers of the ages visible in the buildings, monuments, and layout of the town.
Best things about Catania (in my humble opinion): the large and gritty fish market full of salty odors, bright colors, and raucous fishmongers; the lava rock facades on the big and bulky buildings which lend a dark and romantic glow even on sunny days; the wide and super walk-able streets that burst with locals and flicker with light after dark.