Question: How long is the river that bounds the Mid-Continent Region on the west?

Context articles: Andrus Island
Turweston
Mid-Continent Region (North America)
Jerantut District
Willapa Hills
Araucanía (historic region)
Missouri River
Spavinaw terrane
River Garry, Inverness-shire
Summit League

Andrus Island is an island in the Sacramento-San Joaquin River Delta in Sacramento County, California, twenty kilometres northeast of Antioch.
 The 3000 ha island is bounded on the north, and northwest by the Sacramento River, on the west, Georgiana Slough, on the southeast, Mokelumne River, and San Joaquin River, on the southwest Jackson Slough, and Seven Mile Slough.
 The island is entirely within the bounds of the immense Rio Vista Gas Field, although well drilling pads and associated infrastructure make up only a small part of its land use, which is mainly agriculture.
Turweston is a village and civil parish in the Aylesbury Vale district of Buckinghamshire, England.
 The village is beside the River Great Ouse, which bounds the parish to the north, west and south.
 Turweston is the most northwesterly parish in Buckinghamshire: the Ouse here forms the county boundary with Northamptonshire to the north and west and Oxfordshire to the south.
 Across the river the Northamptonshire market town of Brackley is just west of Turweston, with the town centre about 1 mi west of the village.
 The parish has an area of 1295 acre and the 2011 Census recorded a parish population of 211 people.
The Mid-Continent Region of the United States is a physiographic province that extends from northern Texas and covers portions of Nebraska, Kansas and Oklahoma.
 This area is a transition between the Eastern Plains and drier, short grass prairies of the Great Plains Region.
 It is bounded by the Mississippi River on the east and the Missouri River on the west and consists of generally low-relief, flat-lying marine and stream deposits from the Mesozoic and Cenozoic Eras.
 Geologically, the area is tectonically stable and part of the continental core.
 It has been impacted by structural folding, faulting, deformation, erosion and sedimentation from the ancient, eroded mountains of the Ouachita-Ozark Highlands in the southern portion of the region.
 The region has significant oil and gas production in the Arbuckle, Arkoma, Nemaha Uplift, and Ouachita Mountain areas, but lacks production and has little exploration outside of these areas.
The Jerantut District (Chinese: 而连突) is a town, a parliamentary constituency and a district in north-eastern Pahang, Malaysia.
 Jerantut is the main entrance to the National Park.
 Being the largest district in Pahang, it bounds the northern states of Kelantan and Terengganu, in the south, Temerloh and Maran district, in the west, Lipis and Raub district and in the east, Kuantan district.
 Tembeling River, the main river in this district is the exciting way to National Park and the surrounding villages in Ulu Tembeling.
 The joining of Tembeling and Jelai river forms the Pahang river where it flows right through the Royal Pekan town and then through the South China Sea.
The Willapa Hills is a geologic, physiographic, and geographic region in southwest Washington.
 When described as a physiographical province, the Willapa Hills are bounded by the Pacific Ocean to the west, the Columbia River to the south, the Olympic Mountains to the north, and the Cascade Range to the east.
 Some definitions place the Puget Lowland physiographic province east of the Willapa Hills.
 Included within the province are the Black Hills, the Doty Hills, and a number of broad river valleys, some of which open up into broad estuaries on the Pacific such as Grays Harbor and Willapa Bay.
 Other definitions do not include the Black Hills.
 The USGS GNIS defines the Willapa Hills as bounded by the Columbia River to the south and the Chehalis River to the north, without giving specific east and west bounds.
 The Willapa Hills are one of the Pacific Coast Ranges, which continue north as the Olympic Mountains and south, across the Columbia River, as the Oregon Coast Range.
Araucanía or Araucana was the Spanish name given to the region of Chile inhabited by the Mapuche peoples known as the Moluche (also known as Araucanos by the Spanish) in the 18th century.
 Prior to the Spanish Conquest of Chile, the lands of the Moluche lay between the Itata River and Toltén River.
 Following the great rising of the Moluche and Huilliche after the Battle of Curalaba in 1598 during the Arauco War, the Spanish were expelled from south of the Bío-Bío River.
 After many decades of further warfare, the bounds of Araucania were recognized by the Spanish as being between the Bío-Bío River and Toltén River.
 This old region of Araucanía now is divided between the southern part of the Bío-Bío Region and the Araucanía Region, in southern Chile.
The Missouri River is the longest river in North America.
 Rising in the Rocky Mountains of western Montana, the Missouri flows east and south for 2341 mi before entering the Mississippi River north of St. Louis, Missouri.
 The river takes drainage from a sparsely populated, semi-arid watershed of more than half a million square miles (1,300,000 km), which includes parts of ten U.S. states and two Canadian provinces.
 When combined with the lower Mississippi River, it forms the world's fourth longest river system.
The Spavinaw terrane is an occurrence of Proterozoic (1.40–1.35 Ga) intrusive and volcanic rocks in the mid-continent region of the United States.
 The terrane extends across southern Missouri, southern Kansas, northern Arkansas and much of Oklahoma.
 The rocks are almost entirely known from drill core and only exposed in outcrop near Spavinaw, Mayes County, Oklahoma and parts of the Saint Francois Mountains in Washington County, Missouri.
 The terrane is composed almost exclusively of essentially unaltered intrusive granites and volcanic rhyolite and rhyolite tuffs.
The River Garry (Scottish Gaelic: "Garadh / Abhainn Gharadh" ) in Invernessshire is a long river punctuated by a series of long Lochs, in Lochaber.
 Many of the Lochs are part of a 1960s hydroelectricity scheme.
 The river begins in The Rough Bounds, and proceeds into Loch Quoich, from where it heads east until it joins the River Kingie at the Kingie Pool.
 From there it flows into Loch Poulary, and thence to Loch Garry.
 The final section is 3.5 mi long, and runs into Loch Oich (part of the Great Glen) just east of the village of Invergarry, through which it runs.
 Invergarry is the near the site of the 17th century Invergarry Castle; a website showing the village and the river in detail from the air exists at www.myglengarry.com .
The Summit League, or The Summit, is an NCAA Division I intercollegiate athletic conference with its membership mostly located in the Midwestern United States from Indiana and Illinois on the East of the Mississippi River to the Dakotas and Nebraska on the West, with additional members in the Western state of Colorado and the Southern state of Oklahoma.
 Originally dubbed the Association of Mid-Continent Universities in 1982, on June 1, 2007, the conference changed its name from the Mid-Continent Conference.
 League headquarters are in Elmhurst, Illinois.