Yangon is roughly 390 miles (625 km) south of Bagan. The journey from the templed city can take anywhere from a 1.5-hour flight to an 18-hour train ride.
Traveling by plane is the quickest way, although if you factor in additional time getting to and from the airport, it ends up closer to 4 hours (but still by far the fastest). Trains are the slowest and least comfortable, although they're typically also the cheapest. In the middle you have options such as renting a car, hiring a driver, or taking a bus.
Duration: 1 hour 20 minutes
If you're looking for the quickest and most convenient way to travel between Bagan and Yangon, going by plane is surely it. The flight takes less than an hour and a half, and with ground transport to the airport and security, you can do the whole trip in about 4 to 4.5 hours.
Flights are operated by numerous airlines including Myanmar Airways International (MAI), Mann Yadanarpon Airlines, Myanmar National Airlines, and Air KBZ. They depart from Nyaung-U Airport (NYU) which is roughly 20 minutes from Old Bagan and land at Yangon International Airport (RGN), just 30 minutes west of the main part of the city.
By Private Vehicle
Duration: 8.5 to 9 hours
If you prefer road travel, you also have the option of going by private vehicle between Bagan and Yangon. This is typically the second-most convenient form of transportation. To do this, you can either rent a car or hire a driver. In both scenarios, you will take Route 2 (also called Anawrahta Road) north to Nyaung-U, then hop on the Yangon-Mandalay Expressway south to Yangon.
Duration: 10 hours
There are a number of VIP buses that travel between Bagan and Yangon including JJ Express, Elite Express, Mandalar Minn, Khaing Mandalay, and Bagan Min Thar. All of them have air conditioning and most feature comfortable reclining seats and ample legroom. Some will pick you up at your hotel while others meet you at the bus station. The route takes about 10 hours.
Duration: 17.5 hours
The final option for getting from Bagan to Yangon is to hop on a train; however, it's extremely slow and known to be bumpy, cramped, and uncomfortable. Trains leave Bagan in the late afternoon via Myanmar Railways and arrive in the morning at the train station in Yangon. Tickets don't cost much less than bus tickets which are far more comfortable so unless oyu're on an exceptionally tight budget, buses usually make more sense.