Las Vegas is 3 times larger than Salem, Oregon.
Area: 363 km2 calculated
Las Vegas, officially the City of Las Vegas and often known as simply Vegas, is the most populous city in the state of Nevada and the county seat of Clark County. Wikipedia
Area: 123 km2 calculated
Salem is the capital of the U.S. state of Oregon, and the county seat of Marion County. It is located in the center of the Willamette Valley alongside the Willamette River, which runs north through the city. Wikipedia