The Bellagio Fountain show is one of the cornerstones of the Las Vegas experience, and draws huge crowds daily for the free musical spectacle. The choreographed water dance takes place every half hour during the week - every 15 minutes on the weekends - and includes impressive visual effects like rolling mist and laser lights. After dark is probably the best time to visit, in order to better see the lights, but it's a fun activity any time of day.