There's a reason why you've heard of The Venetian. In my opinion, it is the most architecturally brilliant hotel on The Strip. You will find yourself walking around aimlessly, staring anywhere but where you're walking.
Shop around The Grand Canal Shops which lead into St Mark's Square.
Try a gondola ride. We tried the outdoor one which was 10 minutes and $12.50. The indoor rides are 15 minutes and a couple dollars more. I had no idea that the gondoliers serenade you in Italian. Our gondolier, Aldo, had a beautiful voice but all the ones that I overheard sounded wonderful as well. I got goosebumps when we passed under a small bridge and Aldo's voice strengthened with the reverberation.
Madame Tussaud's Wax Museum is also on the premises, but I did not visit, having seen the London version and not having the time.