I'm staying in Seattle for 4 days, 29 August to September 1. (Had a plan to go to Waterton Lakes but that's seeming too hard). I'm keen to do some good, staunch day hikes. (Perhaps overnight.) Mt Si and Mt Ranier seem two destinations. Can anyone give me up to date information about public transport options from downtown Seattle to get to either or both of these? And which walks stand out? Yes I know there is also a lot to see in Seattle itself, but I'm keen to get walking in preparation for a trip to Glacier National Park.

Look here: https://www.mountaineers.org/explore...#c4=Day+Hiking

You might be able to connect to someone to share transportation. Getting to trailheads using public transportation is going to be your biggest problem.

I agree with the Mountaineers suggestions. We have been members of that group for many years and their outings are great.

Mt Si is a hike that I personally really like, except for the many people. It is right in the metro area, so gets a ton of people. Rainier does too, but there are many trails there so people are dispersed a bit, which is not the case at Mt Si.

Thanks - I'd never heard of the Mountaineers, will definitely make contact. It looks like someone from overseas is welcome to join in?

The Mountaineers is the local hiking/climbing club. They do let nonmembers join on some outings, depending on skill level. So for basic hikes, it is very easy to join in as long as there is room. They do carpool, so be sure to explain that you are looking to join a ride and be willing to share costs.