Antigua's principal pleasure is walking its cobblestone streets and discovering the layered ruins: colonial churches whose facades were rebuilt while their naves remain open to the sky, convents whose cloister gardens are now hotel patios, and baroque arches built for nuns who weren't supposed to be seen. The city itself is the attraction.
Beyond the street-level spectacle, the volcanoes that ring the city offer serious trekking. The overnight climb up Acatenango, watching Fuego erupt through the night, is one of the defining experiences of Guatemala.