200 Second Avenue North
Seattle, Washington 98109

From Pacific Science Center's events listing:

Be a part of a Northwest family tradition at the 33rd Annual Model Railroad Show. See all your favorite layouts of various scales, ride a kid-sized choo choo, learn all about train safety and enjoy many other fun train related activities! Produced in cooperation with the National Model Railroad Association, Pacific Northwest Region, 4th Division.
Show runs 10:00 a.m. to 6:00 p.m. each day.

Admission included in regular PSC entry fees; see event home page for more information.

Official Website: http://www.4dpnr.org/PSCshow.htm

Added by donnunn on December 22, 2006