The Lyon Building is a historic building located at 607 Third Avenue in Downtown Seattle, Washington, United States. It was built in 1910 by the Yukon Investment Company and was named after the city in France of the same name, reflecting the French heritage of the company's owners. It was designed by the firm of Graham &amp; Myers in the Chicago school style of architecture and was built by the Stone &amp; Webster engineering firm, whose use of non-union labor would make the unfinished building the target of a bombing by notorious union activist John B. McNamara, who would commit the deadly Los Angeles Times bombing only 1 month after. The Lyon Building was luckily not destroyed due to its substantial construction, and after little delay, it was completed in 1911 and soon became one of Seattle's most popular office addresses for lawyers and judges due to its proximity to Seattle's public safety complex and the King County Courthouse. It was the founding location of many foreign consuls, social and political clubs as well as the City University of Seattle. The building's basement now serves as an entrance the Pioneer Square station of the Seattle Transit Tunnel. The Lyon Building was added to the National Register of Historic Places on June 30, 1995 and was designated a Seattle landmark on August 16, 1996. In 1997 it was converted to residential use as a shelter and services center for the homeless and at-risk by the non-profit Downtown Emergency Service Center, who are the current owners of the building.