this is a fun trip that includes Amtrak train to get to ewr for your connecting flight to hong kong.
United Airlines have round trip travel from Philadelphia (PHL) to Hong Kong (HKG) from $512 that includes train tickets from PHL to EWR to catch your flight....or $526 no train option. I attached screenshots for both options below.
Departs PHL: Monday thru Thurs beginning Jan 9 thru Feb 15 and then again Feb 26 thru May 23, 2018
Returns: wide and good availabiity
Book this with United Airlines [united.com]
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