Originally Posted by indyfabz

Amtrak freight from Philly to Seattle may be another option available to you. You have to call and check if they offer freight for that O-D pair. The nice thing about an Amtrak box is that requires relatively little disassembly of the bike.

This place is one block from the train station:

http://www.hiusa.org/seattle

I twice stayed at the old location before tours. It had secure pens in the basement for storage of bikes and bike boxes. Maybe this has something similar. It was very popular so advance reservations were neessary.