Fly from New York-JFK to Seoul, South Korea for $509 roundtrip on Air China this winter and spring.
Searching on the Air China website you should be able to find departures at this price point on select days starting in late November through April 30, 2019. Peak holiday dates and many weeks in January are blacked out at this rate.
Flights on other airlines are nearly double the amount for similar dates! So take advantage of this sale while you can, tickets must be purchased by November 30th.
Usually, Air China has a long layover at its hub in Beijing (PEK), but for this route, there are some convenient and quick layovers on most itineraries. As an example, I found seats departing JFK on Saturday, March 2 and returning from ICN on Wednesday, March 13, 2019, with just a few hours between connecting flights. February and March seem to have the most inventory available.
Need a place to rest your head in Seoul? Here's what's available for the listed dates on Hotelwatchdog.