Colorado → Arizona · Interstate 70 / Interstate 25
Tackling the 1173 km (729 miles) that separate Denver, Colorado, from Tucson, Arizona, in a single push demands long-haul planning: 11h 10m behind the wheel along Interstate 70 / Interstate 25 exceeds the safe ceiling on continuous driving. Schedule a midpoint overnight, driver swap (where applicable) and a mandatory pre-trip inspection. Pulling out of Denver (the Mile-High City and economic center of the Rocky Mountain region) toward Tucson (the second-largest city in Arizona and gateway to the Sonoran Desert), total fuel use reaches 106.6 liters (28.2 gallons) of regular unleaded (about $98.07), on top of consecutive tolls and a probable hotel night. Gross outbound reimbursement, against the IRS standard mileage rate (2025) schedule of $0.43/km, lands at $504.39. Capture lodging and meals in separate fields of the Clara receipt so they don't get tangled with the pure mileage calculation. The typical corporate policy authorizes a hotel per-diem up to a certain ceiling and meals with a limit per occurrence, amounts that must be substantiated with a fiscal invoice in the contributor's or the company's name. Confirm before the trip the prevailing ceiling per the internal HR table, and verify that the chosen hotel issues an invoice in the format the corporate fiscal system accepts, avoiding later disallowance of the amount.