Nevada → Arizona · Interstate 15
On heavy-rain or dense-fog days the Las Vegas, Nevada, to Tucson, Arizona, leg routinely demands well more than the 6h 33m estimated: Interstate 15 carries known hydroplaning hot spots and reduced-visibility corridors that justify dropping to 35 mph through a few short stretches. The outbound run covers 687 km (427 miles) over varied topography between Las Vegas (the leading entertainment and conventions destination in the US Southwest) and Tucson (the second-largest city in Arizona and gateway to the Sonoran Desert), demanding sharper attention on mountain descents and shoulder-less curves. Before pulling out, check brake-pad wear, tire tread depth, and washer-fluid level in the reservoir. Fuel spend holds near $57.50 for the 62.5 liters (16.5 gallons) consumed. Even in adverse conditions, the flat tariff of $0.43/km guarantees the standard outbound payout of $295.41 — log any incidental costs (extra toll, mandatory meal, emergency lodging) in a separate field on the Clara receipt.