Yes, you can leave the airport during a layover in 2026, and in most cases, you do not need to worry about your checked baggage. If your flights are on a single ticket and the layover is less than 24 hours, your bags are typically "checked through" to your final destination and will stay with the airline. You can simply walk out of the airport (provided you meet the entry/visa requirements of the country you are in). The major exception is the United States and Canada: even if you are just "transiting" through to another country, you must collect your bags to clear customs and then re-check them immediately at a transfer desk before you can leave the airport or head to your gate. If you have a very long layover (e.g., overnight) or are on separate tickets ("self-transfer"), the airline may require you to claim your bags, in which case you would need to store them in a "Left Luggage" locker at the airport.