Las Vegas is a tourist city and is the destination that millions of visitors choose every year. Because of the popularity of the attractions of Las Vegas, visitors come to the city expecting glittering lights and casinos, but few realize that it is also the perfect place to start a tour of national parks of the southwestern United States.
The reasons are simple because Las Vegas is such a popular destination in its own right, the volume of flights in and out of the city are not only more plentiful than other nearby cities, but also far less expensive.
Also, there are many more hotel and restaurant choices in Las Vegas than in neighboring cities like Salt Lake City, making it an obvious choice for a starting point for anyone who wants to not only explore it but also the national parks that are within driving distance. This will include the majority of national parks in Utah, Arizona, and California.
This proximity means you can begin your journey in your hotel room in the morning and be in Zion by afternoon. It is speculated that this proximity to Las Vegas is the reason that Zion is so much more heavily visited than Bryce, which is more remote.