Wikipedia:Today's featured article/September 24, 2017

The Downtown Seattle Transit Tunnel is a public transit tunnel for buses and light rail trains in Seattle, Washington, in the United States. It runs north–south through Downtown Seattle, connecting five stations on 3rd Avenue and Pine Street. It is the busiest section of Sound Transit's Link light rail network, with an average of over 10,000 weekday train boardings at the four stations served by light rail. The $469 million tunnel was planned in the late 1970s and built between 1987 and 1990, using tunnel boring machines and cut-and-cover excavation. Between 1990 and 2004, the tunnel was exclusively used by dual-mode buses that ran on overhead wires; they were later replaced with hybrid electric buses using batteries within the tunnel. After a two-year renovation, the tunnel reopened on September 24, 2007, and light rail service began in July 2009, sharing the platforms with existing buses. Planned expansion of the light rail system, along with the closure of one station, will necessitate the removal of buses from the tunnel by 2019.