Can you walk from the Venetian to the Aria? Certainly. I’ve done it many times, and it takes anywhere from 20 minutes to 1/2 hour, depending on how fast you stroll. Google maps says it takes 21 minutes, but that’s just to the outside of the City Center resort on the Las Vegas Strip.
To get inside the actual Aria Hotel and Casino itself, means a walk through the Crystals, the upscale shopping center at City Center. And the walk from the Strip entrance of Crystals to the Aria entrance is another 700 feet or so, or roughly .13 mile, which will tack on another few minutes.
To check out the entire strip and take in all of the sights on your way, just simply walk down the east side of the Strip (the side the Venetian is on), all the way down to Planet Hollywood. You’ll then use the above-ground pedestrian walkways to stroll over to the Crystals entrance, and from there, the Aria.
A faster way is to walk down the east side of the strip to Flamingo Boulevard, (the road inbetween Caesars Palace and the Bellagio). Take the pedestrian walkway over to the Bellagio, walk through the casino to the free tram (there are signs pointing to it everywhere), and take the free monorail to the Aria. This is also a much more enjoyable walk if you are doing it during one of those notoriously hot Las Vegas summer days.
Driving from the Venetian to the Aria could take just a few minutes, or 1/2 hour (depending on Strip traffic). Mapping systems estimate it to be a five minute drive. This doesn’t take into account the distance from the large parking garages at each resort to the casino itself.
Another option is to take the Deuce, the Las Vegas bus system. It also takes about 25 minutes. A bus stop is just across the street from the Venetian (just to the North, going towards Treasure Island – you’ll see it marked). It stops at the Cosmopolitan, giving you a short walk to the Crystals entrance, and from there to the Aria.