It incorporates a heritage railway, historic depot, exhibit hall, library, and collection care center, and serves more than 130,000 visitors per year.

An atypical design was the result of the need for a rural combined freight-passenger depot, however, one with lavish decorations to reflect the holiday spirit of vacationers from Seattle.

The current structure was modified from the original, in which the bay window continued up through the roof and formed an octagonal tower a full story in height.

A large swept dormer was placed in the southern part of the main structure above the freight section, Cast iron cresting and fancy butt shingles decorated the roof of both the main body and the transverse dormer.

One of the items included is the Messenger of Peace Chapel Car which is listed on the National Register of Historic Places.

The Northwest Railway Museum maintains 18 passenger cars of various time periods, manufactured between 1881 and 1998.

Several of the passenger cars operate with one of the museum's 2 RS4-TCs and/or Northern Pacific 924 for excursion service on the Snoqualmie Valley Railroad.

The museum owns a total of 39 other railway equipment artifacts in various forms, previously operating for a wide variety of railroads.

This 5-mile (8 km) route allows museum visitors to experience a train excursion aboard antique railroad coaches dating to 1915 and earlier.

It features 8,200 square feet (760 m2), two full-length inspection pits, and is used to perform many functions once conducted in railroad backshops.