The route itself is a little known leg in the Kenmore Air route map. It is a nine mile, as the plane flies, jump from Lake Union in Seattle to Kenmore Air's main base in Kenmore. It is the shortest commercial flight I have ever been on or may ever be on.
The price to fly? $40, total.
The flights themselves are short, lasting about 15 minutes in each direction. You do get a little more time in the air and see more if you book the scenic tour for $100 a person, but a round trip from Lake Union to Kenmore can be a cheaper and just as interesting alternative (All of the photos in this post were taken from the flight I was on).
Booking this little round trip does, however, require a little work. It is not a "normal" route that pops up on the website, but it can be booked online via their booking system. The link to connect directly to the booking system is here. The ticket and route is legit, as my photos here prove.
One work of caution is that while you can do a tight turn around like we did where you depart, arrive, and immediately turn around to fly back, there is a risk that your flight will be delayed going up. That almost happened to us, so it is probably advisable to to leave time in between the flights. It depends on how much you want to live on the edge. If you do leave time, you have the option of walking over to the 192 Brewing Company Tap room for a beer or two. There is not a lot to do in Kenmore, so don't plan an entire day there!
*Even a flat rate taxi is $31 for the trip. Uber estimates that it would be between $23-31 for a one way trip, but you could make it less using their first ride up to $30 free deal.