The MOHAI museum in Seattle, Washington has a very rare piece of aviation history hanging from its ceiling. The wooden Boeing B-1 seaplane on display (built in Seattle in 1919) was the only one ever built, yet it had a very successful and long career.
Boeing designed and built their first aircraft in 1916 (the B&W Seaplane) and by 1919 they had really started to hit their straps in aircraft design. The B-1 first flew on December 27th, 1919 and for 8 years, pilot Eddie Hubbard ran the mail from Seattle up to Victoria, British Columbia in Canada using the B-1 on what became the first regular international airmail route. The airframe outlived 6 engines and covered 563,270 kilometres / 350,000 miles in that 8 years! Pretty impressive for a relatively small all wooden biplane!
The B-1 mail flights would depart from Lake Union which is just happens to be the lake right next to the new MOHAI museum that relocated there into an old armoury building in late 2012. The B-1 has been beautifully restored and I think it is fantastic that a great piece of aviation history has remained in Seattle and over 90 years later can reside right next to its former base of operations.