It is served by Amtrak's Cascades, Coast Starlight, and Empire Builder, as well as Sounder commuter trains run by Sound Transit.

The station was designed by Reed and Stem and incorporated elements from various architectural styles, including a prominent clocktower inspired by St. Mark's Campanile in Venice.

As passenger train service declined in the mid-20th century, King Street Station fell into disrepair and was renovated several times to conceal interior elements in the name of modernization.

[2] The current station consists of ten tracks and four platforms, including one that is used by Sounder commuter trains and connected via a pedestrian bridge on South Weller Street.

[3][4] The depot's 242-foot (74 m) tower was modeled after the recently collapsed Campanile di San Marco in Venice, Italy,[5] making it the tallest building in Seattle at the time of its construction.

This tower contained four huge mechanical clock faces built by E. Howard & Co. of Boston, Massachusetts, offering the time to each of the four cardinal directions.

After the end of World War II, as passenger rail travel began to decline across the United States, steps were taken to gradually modernize King Street Station.

In the late 1940s a set of "electric stairs" and a new side entrance to the second floor railroad offices were built over the open stairwell to Jackson Street, narrowing them by half.

In the late 1950s the station's original high-back benches, made of yellow oak, were replaced by modern chrome and plastic seats.

[9] The dedicated women's waiting room at the southwest corner of the building was converted into employee offices; its own architectural details suffering the same damage.

The only original remaining features left visible in the main waiting area were the terrazzo tile floor and the clock on the west wall above the restrooms.

To further cut costs the station's restaurant, lunch counter, and gift shop were immediately closed and vending machines installed.

Many King County Metro and Sound Transit Express bus routes serve the area, and the First Hill line of the Seattle Streetcar network stops nearby.

New brass door hardware and reproduction period light fixtures and plaster decorative work were included to reproduce the former character of the station's interior.

[19] In October 2010, the King Street Station project was awarded $18.2 million from $2.4 billion in high-speed intercity passenger rail service funding announced by the U.S. Transportation Department.

[22] King Street Station is a red brick masonry and steel frame building with terra cotta and cast stone ornamentation, through relatively subdued in comparison to the clock tower.