[5] Located in a valley and bisected by Interstate 90, the city is bordered by the Sammamish Plateau to the north and the "Issaquah Alps" to the south.

"Issaquah" is an anglicization of the Southern Lushootseed placename /sqʷáxʷ/, meaning either "the sound of birds", "snake", or "little stream".

[8][9][10] In September 1885, the then-unincorporated area was the scene of an attack on Chinese laborers who had come to pick hops from local fields.

[12] Initially a small mining town, the city has changed noticeably both in its appearance and economic focus.

Issaquah was originally developed to service the mining industry (on the two nearby mountains that now lend their names to the Cougar/Squak Corridor Park), and began as the town of "Gilman".

As the mining deposits neared depletion in the late 1890s, other companies started to realize Issaquah's potential to support a lucrative lumber business.

These companies exported timber from Issaquah and other small, local towns to Seattle and larger, rapidly growing communities throughout western Washington.

Microsoft and other technological industries moved into Redmond and other cities in the area, and later established operations in Issaquah itself.

[citation needed] In June 1996, Costco moved its global headquarters to Issaquah from nearby Kirkland.

[14] Issaquah is located 15 miles (24 km) east-southeast of Seattle at the south end of Lake Sammamish.

[citation needed] Issaquah has a warm-summer Mediterranean climate (Köppen: Csb) with chilly, extremely wet winters and warm, moderately humid summers.

[21] Other major Issaquah employers include Microsoft, Siemens Medical Solutions' Ultrasound Group, Overtime Technologies, Boehm's Candies, and Darigold.

According to the Washington State Office of Financial Management, Issaquah ranked 6th of 279 eligible incorporated communities in population growth between 2000 and 2005.

Issaquah is bisected by Interstate 90, which runs from Seattle to Boston, and Washington State Route 900, which connects the city to neighboring Renton.

Proposals have been made to create a bypass, but opponents have argued that this will only result in more sprawl in the area beyond downtown and thus bring in more traffic and pollution.

In addition, King County has no funding in its seven-year capital plan to improve Issaquah-Hobart Road, the southern terminus of the proposed bypass.

Bus service in Issaquah is provided by King County Metro as well as regional Sound Transit routes to Seattle and Bellevue.

[27][28] Since August 1995, the city and King County Metro provided a free circulator bus (route 200) between business districts and community centers in Issaquah as a form of traffic congestion relief.

It was originally located in a converted movie theater and later built its main stage at the Francis J. Gaudette Theatre in 1993.

[44] The High Alpine Chapel opened in 1981 on the grounds of the Boehm's candy shop near downtown Issaquah.

[47] In 2023, Issaquah became the first Washington city to be awarded LEED Gold certification for its environmental conservation and sustainability initiatives.

Swedish Medical Center opened a full-service hospital and healthcare facility in the Issaquah Highlands with a capacity of 175 inpatient beds and a 24-hour emergency room in November 2011.