211 First Ave. S., Seattle, WA 98104
Milepost 31 highlights the people and projects that shaped Pioneer Square and provides an inside look at the SR 99 Tunnel Project. Visitors to Milepost 31 will find more than just construction photos and brochures. You’ll find history, artifacts and interactive exhibits designed to broaden your understanding of the land beneath you. You’ll explore the neighborhood’s changing landscape, from earth-moving efforts of the past to the massive tunnel project that will soon move State Route 99 underground and reconnect Pioneer Square to the waterfront.
Milepost 31 will remain open after its normal operating hours to participate in First Thursday activities. Refreshments will be provided.