Being the land of virtually no water, it's nice to know that the residents of LV have many (chlorinated) swimming options, one of the best being, Garden of the Gods at Caesar's Palace.
This pool has many sub-pools, levels, and fountains, each of which is named after a Greco-Roman deity. Gets great sun, at any time of the day till sundown. When I was there, a DJ played a flurry of house, breaks, and dubstep, which made for an upbeat and lively atmosphere. Seating is painfully limited (if it looks any nicer than an outdoor lounge chair, you gotta pay up), but the enormous bowl-sized cocktails made up for that transgression, in my book.