Question: UFC Fight Night: Namajunas vs. VanZant was held in what county?

Context articles: UFC Fight Night: Marquardt vs. Palhares
UFC Fight Night: Condit vs. Kampmann
UFC Fight Night: Gustafsson vs. Manuwa
Fox UFC
UFC Fight Night: Namajunas vs. VanZant
UFC Fight Night: Florian vs. Gomi
UFC Fight Night: Maynard vs. Diaz
UFC Fight Night: Silva vs. Irvin
Las Vegas
UFC Fight Night 6

UFC Fight Night: Marquardt vs. Palhares (also known as UFC Fight Night 22) and originally scheduled as UFC Fight Night: Maia vs. Belcher, was a mixed martial arts event held by the Ultimate Fighting Championship on September 15, 2010 at the Frank Erwin Center in Austin, Texas.
 The event also served as a lead in to the season premiere of "".
UFC Fight Night: Condit vs. Kampmann (also known as UFC Fight Night 18) was a mixed martial arts event held by the Ultimate Fighting Championship (UFC) on April 1, 2009.
UFC Fight Night: Gustafsson vs. Manuwa (also known as UFC Fight Night 37) was a mixed martial arts event held on March 8, 2014, at The O2 Arena in London, England.
 The event was shown live in the UK on Channel 5 and BT Sport and in the United States on UFC Fight Pass.
Fox UFC Fight Night (previously referred as Fox UFC Saturday for broadcasts on Fox or FS1 UFC Fight Night for broadcasts on other Fox-owned properties) is the branding used for telecasts of mixed martial art competitions from the Ultimate Fighting Championship (UFC) that are produced by Fox Sports.
 Previously, "UFC on Fox" was also used as a blanket title for UFC events aired on the Fox network, although since the concurrent launch of Fox Sports 1 and rebranding of Fuel TV as Fox Sports 2 in August 2013, all live UFC broadcasts on Fox-owned networks (including preliminaries, "UFC Fight Night" and "The Ultimate Fighter Finale") have since used the name.
UFC Fight Night: Namajunas vs. VanZant (also known as UFC Fight Night 80) was a mixed martial arts event held on December 10, 2015, at The Chelsea at The Cosmopolitan in Las Vegas, Nevada.
UFC Fight Night: Florian vs. Gomi (also known as UFC Fight Night 21) was a mixed martial arts event held by the Ultimate Fighting Championship on March 31, 2010 at Bojangles Coliseum in Charlotte, North Carolina, This was the third time the UFC held an event in Charlotte, but the first since UFC 5.
UFC Fight Night: Maynard vs. Diaz (also known as UFC Fight Night 20) was a mixed martial arts event held by the Ultimate Fighting Championship (UFC) on January 11, 2010 at the Patriot Center in Fairfax, Virginia.
UFC Fight Night: Silva vs. Irvin (also known as UFC Fight Night 14) was a mixed martial arts event held by the Ultimate Fighting Championship (UFC) on July 19, 2008 at the Palms Casino Resort in Las Vegas, Nevada.
Las Vegas ( , Spanish for "The Meadows"), officially the City of Las Vegas and often known simply as Vegas, is the 28th-most populated city in the United States, the most populated city in the state of Nevada, and the county seat of Clark County.
 The city anchors the Las Vegas Valley metropolitan area and is the largest city within the greater Mojave Desert.
 Las Vegas is an internationally renowned major resort city, known primarily for its gambling, shopping, fine dining, entertainment, and nightlife.
 The Las Vegas Valley as a whole serves as the leading financial, commercial, and cultural center for Nevada.
UFC Fight Night: Sanchez vs. Parisyan (also known as UFC Fight Night 6) was a mixed martial arts event held by the Ultimate Fighting Championship on August 17, 2006.
 The event took place at the Red Rock Resort Spa and Casino in Las Vegas, Nevada, and was broadcast live on Spike TV in the United States and Canada.
 It acted as a lead-in to the season four premiere of "The Ultimate Fighter".
 The two-hour broadcast of UFC Fight Night 6 on Spike TV drew a 1.5 overall rating.