The Pacific International (“P.I.”) Livestock Association constructed the original buildings found on the site during the early 1920’s. Meat processing plants, stockyards and related structures were all built along the banks of the Columbia Slough that supported this uniquely “western” industry. These original buildings were lost in a fire three years after their completion, but were quickly rebuilt. Along with the Portland Union Stock Yards Company, each prospered through the 1930’s, establishing the “Expo” as the largest livestock exposition of it’s kind on the west coast. The facilities housed not only livestock expositions, but became home to many auctions and first class rodeos. During World War II, the facility became the temporary home for more than 3,500 Japanese-Americans for five months in 1942. Becoming known as the “Portland Assembly Center,” the center was used in this dark capacity until facilities in Hunt, Idaho were constructed to accept these Americans closing a sad chapter in the centers history.

The P.I.’s popularity continued through the fifties and sixties until emerging markets began to affect the livestock industries. Multnomah County purchased and began remodeling the property in 1965, renaming it the Multnomah County Exposition Center. The Multnomah County Fair moved the to the site in 1969 as well as an increasing number of consumer events. This slow growth continued through the eighties with the addition of trade shows, further remodeling efforts and the continued establishment of a strong market identity. By 1990, the facilities long decline in capital improvements had realized a downturn in business with the 1990 opening of the Oregon Convention Center.

In 1997, Metro and MERC took the first steps in revitalizing the aging complex of buildings it inherited from Multnomah County when they assumed management in 1994. A series of fortuitous circumstances enabled Metro to fund and construct a new 108,000-square-foot exhibition facility, Hall E, which opened in the spring 1997. This modern facility has all the required amenities: column-free exhibit space, temperature control systems, loading bays, a large lobby and meeting rooms. The completion of Hall E gave the Expo Center the distinction as the largest consumer show complex on the West Coast. The Center successfully hosted America’s Smithsonian an immediate showcase event to the new facility.

During the construction of Hall E, it became evident that a long-term vision for the Expo Center was needed. A vision planning document, Expo: a Vision for the Future, was created, calling for complete replacement of the remaining four older buildings, Halls A, B, C and D, with modern facilities similar to Hall E. The planning concept would replace the old buildings in phases, with Hall E being the first of three phases.

In 2000, Expo Center simultaneously undertook a master planning process and started construction on Phase 2, the replacement of Hall D. In March of 2001, Hall D was completed as a new 112,000-square-foot building comprising 72,000 square feet of column-free exhibit space, a commercial kitchen, a large lobby and eight meeting rooms. The conditional use master plan was approved by city of Portland in June 2001. It identifies future improvements related to Phase 3 and other required enhancements to the exhibit complex. Concurrent with the master planning process, Tri-Met received funding and community approval to extend its light- rail system with the northern terminus located at the Expo Center. The Interstate MAX (IMAX) light rail project completed in 2004. This, along with over 2000 regional hotel rooms, and area shopping, make the Expo Center a unique destination for quality events - large and small, indoors and out. The Expo Center is managed and operated by the Metropolitan Exposition-Recreation Commission (MERC) (www.mercvenues.org) and is a service of Metro regional government (www.oregonmetro.gov)