Guided viewing platform tours
Interested in seeing the project from up close? We offer several different types of tours out of the Milepost 31 information center, located at 211 First Ave. S. in Pioneer Square.
All of the tours are free but are limited in size and advance registration is strongly recommended (except the self-guided tour).
Winter 2016-2017 update for tour attendees: Two-hour parking vouchers are available at Milepost 31 while supplies last. Additional details are available here.
Join us for a free public tour to see SR 99 tunnel construction at the tunnel’s south end. In addition to learning about our efforts to replace the viaduct, visitors will be treated to views of this massive project from a section of the Alaskan Way Viaduct that has been permanently closed to traffic. Note: this tour does not go down into the tunnel.
The tour takes 60 minutes and is offered on the following days and times:
- Tuesdays: Noon and 5:30 p.m.
- Wednesdays: Noon
- Thursdays: Noon
- Fridays: Noon
- Saturdays: Noon and 3 p.m.
The tour starts and ends at Milepost 31 in Pioneer Square. Parking is available on city streets and in nearby garages. Visit www.downtownseattleparking.com for additional parking information.
Restrictions and conditions
- The tours are 1/2-mile round trip. Visitors must be able to walk over uneven ground and climb up and down 50 stairs.*
- Tour participants must wear sturdy, closed-toe shoes. No sandals, flip-flops, high heels or slip-on shoes allowed.
- Participants are advised not to wear skirts or dresses. Please dress for the weather.
- No one under the age of 13 is permitted. Minors age 13 through 17 must be accompanied by a parent or guardian.
- No pets are allowed.
- All participants must sign a liability waiver on the day of the tour.
- Tours will be conducted rain or shine. In cases of severe weather, such as snow or ice, tours will be cancelled with short notice.
- Tours may be canceled for any reason. We will do our best to accommodate the public on a future tour but we cannot guarantee that there will be space available.
- We reserve the right to deny entrance to anyone not following these rules.
*Because the tour is within an active construction zone, we offer our guests with limited mobility a self-guided tour (pdf 466 kb) along the paved path west of the construction area. Accommodation requests for people with disabilities can be made by contacting the WSDOT Diversity/ADA Affairs team at firstname.lastname@example.org or by calling toll-free, 855-362-4ADA (4232). Persons who are deaf or hard of hearing may make a request by calling the Washington State Relay at 711.
Bike Above Bertha
Join us for a free public bike tour that follows the route Bertha will be taking through downtown Seattle (from above ground, as best as possible). This intimate tour provides a unique way of viewing and understanding the historical, archaeological and engineering aspects of the SR 99 Tunnel Project.
Tours have ended for the year. Check back in spring 2017 for updates.
Scouting and K-12 school group tours
Join Milepost 31 staff for a guided tour of the information center and hands-on activities near the SR 99 tunnel construction site.
Senior center group tours
Bring your group on a guided tour of the information center and to the paved path west of the SR 99 tunnel construction site. These tours are ADA accessible and appropriate for guests with limited mobility.
Take a self-guided tour (pdf 466 kb) of the SR 99 Tunnel Project's massive work zone. Walk or bike along the paved path west of the construction area, near the stadiums. Displays along the path describe construction activities, machinery at work and the area’s history.