Question: Where does the race start that Running on the Sun: The Badwater 135 is about?

Context paragraphs:
2013 Gent–Wevelgem: The 2013 Gent–Wevelgem was the 75th running of the Gent–Wevelgem single-day cycling race.  It was held on 24 March 2013 over a distance of 183.4 km and was the seventh race of the 2013 UCI World Tour season.  The race was originally scheduled to be over a distance of 238 km , but due to snow, the race start was moved from Deinze to Gistel.

Charlie Engle (marathoner): Charlie Engle (born September 20, 1962), is one of the most accomplished ultramarathon runners in the world and author of the riveting memoir "Running Man."  Engle has a track record of winning or placing in many of the toughest endurance foot races across the globe.  He has raced in jungles, summited high ranging mountains and volcanoes, and traversed large expanses of deserts through sand storms.  Among his most notable races in the United States is the Badwater Ultramarathon.  This is an annual race that stretches 135 through Death Valley, California in July.  This punishing race ends after a steep climb of Mt. Whitney.  In the world of Ultramarathons this race, often reaching temperatures around 130 °F is frequently coined "The Toughest Foot Race in the World."  Beginning in the 1990s into the early 2000s, Engle competed in the Eco-Challenge series put on by Mark Burnett (the creator of the wildly popular CBS television series, "Survivor").  The Eco-Challenge took Engle to Borneo, New Zealand, and Vietnam.  The list of Engle's international races is long, but he is most well known for running across the Sahara Desert, from coast to coast, in 2007.  Engle's historic and record setting journey was documented in the film "Running the Sahara", narrated by Matt Damon.  He was joined by two other runners: Ray Zahab of Canada and Kevin Lin of Taiwan.  This transcontinental run through deep sand and politically unstable countries remains one of the premier accomplishments in the ultrarunning sport.  The runners completed over 4,500 miles, averaging over two marathons per day, for 111 consecutive days.

Gerald Tabios: Gerald Tabios (born September 12, 1969) is a Filipino long-distance runner and Ultramarathon runner.  Among his most notable races in the United States is the Badwater Ultramarathon.  This is an annual race that stretches 135 through Death Valley, California in July.  This punishing race ends after a steep climb of Mt. Whitney.  In the world of Ultramarathons this race, often reaching temperatures around 130 °F has frequently coined "The Toughest Foot Race in the World."  Tabios is the first Filipino who is Badwater 135 finisher (new route) and a 4-time Badwater 135 finisher.

Robert Evans (racing driver): Robert Evans (1889 New York City, New York – Unknown) was an American racecar driver.  He drove in the 1911 Indianapolis 500 as a relief driver for Jack Tower, then made a Championship Car race start on the Santa Monica Road Race Course in 1912, finishing second.  He then drove in the 1913 Indianapolis 500 which would be his final Champ Car race.

Everett Saylor: Everett Saylor (8 October 1909 Dayton, Ohio – 31 May 1942 Cape Girardeau, Missouri) was an American racecar driver.  A dirt track racing specialist, he competed in the 1941 Indianapolis 500.  It was his only Championship Car race start.  He was killed in a racing accident on the dirt track at Cape Girardeau.

Entreaty: Entreaty was a black New Zealand-bred Thoroughbred mare, who was unplaced in her only race start.  She produced twelve horses, one of which was Phar Lap.

Badwater Ultramarathon: The Badwater Ultramarathon describes itself as "the world's toughest foot race".  It is a 135 mi course starting at 279 ft below sea level in the Badwater Basin, in California's Death Valley, and ending at an elevation of 8360 feet (2548 m) at Whitney Portal, the trailhead to Mount Whitney.  It takes place annually in mid-July, when the weather conditions are most extreme and temperatures can reach 130 F .  Consequently, very few people—even among ultramarathoners—are capable of finishing this grueling race.

Running on the Sun: The Badwater 135: Running on the Sun: The Badwater 135 is a 2000 documentary film directed by Mel Stuart.  The film follows athletes as they run 135 miles in the 1999 Badwater Ultramarathon, starting in California's Death Valley and ending at Whitney Portal, the trailhead to Mount Whitney.

Elmer T. Shannon: Elmer T. Shannon (2 February 1892 in Stevens Point, Wisconsin – 14 February 1961 in Los Angeles, California) was an American racecar driver.  The 1919 Indianapolis 500 was his only AAA Championship Car race start, though he entered a race at the Sheepshead Bay Race Track later that year but the car did not arrive.  He was primarily a mechanic, engineer, and car builder.

Johnny Unser: Johnny Unser (born October 22, 1958) is a former race car driver.  He is the son of open wheel driver Jerry Unser, cousin of Al Unser, Jr. and Robby Unser, nephew of Al Unser and Bobby Unser, and first cousin once removed of Alfred Unser.  Unser's father, Jerry, died in a racing accident when Unser was seven months old.  He made 5 starts in CART in 1993 and 1994 with a best result of 15th.  He joined the Indy Racing League in its inaugural 1996 season but had a transmission failure during the pace lap of what would've been his first Indianapolis 500 and was not credited with a race start.  In 1997 he made his first start in the Indy 500 starting in the 35th position after league and speedway owner Tony George added his and Lyn St. James' car to the field because slower cars than theirs were guaranteed starting positions because of prior races.  He went on to finish 18th, his best "500" result in 5 starts.  Unser drove the majority of his IRL races for Hemelgarn Racing and in his 14 career IRL starts he had a best finish of 9th in his very first series start in 1996 at Phoenix International Raceway.  His last major open wheel race was the 2000 Indy 500.

Supporting paragraphs: Running on the Sun: The Badwater 135 Badwater Ultramarathon
Answer: Badwater Basin