The Bellagio Fountains are one of the best free attractions in Vegas. The fountains are choreographed to varying pieces of music and light. The show runs every half hour during the day, but on nights and weekends I believe it's every fifteen minutes. I've been fortunate to view the fountain show from the High Roller Observation wheel at the Linq and from a window seat at the Hyde Bellagio lounge. This is an amazing show and not to be missed.