Free city tours when in transit on some airports

Although Dubai airport does not offer free city tours for layovers, it does offer paid tours that are awesome

Normally the university try to book the most direct flight to the conference venue, but too often that means missing out on lots of fun and additional experiences. Years ago, when I booked a flight to Europe via Dubai, the lay-over was more than 8 hours and Emirates took us to a hotel, feed us an brought us back to the airport in time for the connecting flight, which was awesome. The next year the flight schedules changed and the lay-over was shortened but the option for stop-overs (this time not for free) was introduced and ever since we make use of this extra vacation time. 

There are a number of airports that offers city tours for transit passengers free of charge. The Doha city tour takes 3 hours and is free, on a first come-first-serve basis for all passengers with an 8 hour lay-over, travelling on Qatar's airline. If you have a long lay-over in Istanbul traveling on the Turkish airline, you can choose from three tours between 6 to 9 hours. Not that you would want to leave Singapore's Changi Airport, but I you do, have more than 5 hours you can check the schedule for the 6 times per day that the two and an half hour tour departs from the airport.  South Korea,s Seoul Incheon airport provide you with not less than seven options fro tours ranging between one and five hours in length and the Taipei Tayuan airport in Taiwan also offers two daily tours, one departing at 8:00 and the other at 13:30, which will take between 5 and 6 hours to complete. 

The Narita airport in Japan also offers free tours but without transport. The tour takes about 3 hours. The only city in the USA that offers free city tours for lay-over passengers is Salt Lake City in Utah, that offers a 2 hour city tour. 

Most large airports also have city tour options that are convenient and fun such as the Hop On Hop Off tour buses that we now enjoy so much (maybe because we are older and do not like to reinvent the wheel so much each time we set foot on an aircraft, or maybe we became lazy when it comes to certain destinations).