In its earliest years, Casper was regularly flooded by the North Platte River. The city's downtown was located uphill where the flooding wasn't so bad. When the Pathfinder Reservoir was completed in 1909, the city suddenly had a whole area of sandy lowlands located directly west of downtown.
The area was hastily developed during the oil boom of the '20s. Because there were far more jobs than homes, many of the wooden and brick buildings were poorly constructed. Streets in the Sand Bar were left unpaved and many residents lived in tents, according to Walter Jones' 1981 book "History of the Sand Bar."
"The district also became well known as a haven for thieves, burglars, footpads, automobile thieves and safe crackers," Jones wrote. "The 1920s became the heyday of prostitution on the Sand Bar."
Jones wrote there were an estimated 35 prostitution cribs in the Sand Bar.
"In addition, many prostitutes worked in the district's more elaborate parlor houses whose fronts were disguised as legitimate businesses such as rooming houses, cafes and dance halls," he wrote. "The location of most of the district's cribs and parlor houses was common knowledge in Casper.
"So many women worked in the confined quarters of the Sand Bar that attracting customers sometimes was difficult," the book says. "Often the more aggressive women would run out of their places to try to physically drag in a reluctant passer-by."
The district saw a high number of homicides in the '20s, including six gun murders in 1923, Jones said.
"The most brutal slaying ever to take place on the Sand Bar was a hatchet murder that occurred in a shack on Boyer Street in 1927," Jones wrote, noting that the area was nicknamed the "worst bad lands in Wyoming."
A sheepherder and cook named Ed Krchmar was struck in the head nine times with a hatchet before his chest and ribs were kicked in, Jones said. "Indian" Jimmy Sutton pleaded guilty to the murder and was sentenced to life in prison.
By 1925, Casper was bursting at the seams, boasting 40 miles of paved streets, three oil refineries, three railroads and a population of 25,000, according to Irving Garbutt's 2003 book, "I Was There."
Abruptly in 1926, the price of crude oil plunged.
"Payrolls vanished and the economy collapsed," Garbutt wrote. "Almost overnight, around one third of the population pulled up stakes and moved out.
"The town, I found, never really shook off the Great Depression until the Army Air Base was built in 1942, and 10,000 airmen spent their money in Casper," Garbutt wrote. "The Sand Bar's red light district was a big attraction, and the air base commander threatened to call Casper off limits unless it was closed."
According Denver Post columnist Red Fenwick, the job of trying to keep the air base's servicemen away from the Sand Bar's women was like "trying to keep bees out of an alfalfa field when it is in bloom."
"Once the war was over, people began flooding into the 'Oil Capital of the Rockies,' housing became scarce, and the construction industry boomed," Jones wrote. "Once again, oil was the cause."
Today, the Sandbar no longer thrives on vice; after considerable demolition and rebuilding in the 1970s, it became the quiet district of government, business and housing it remains now.
City leaders hope efforts to spruce up the neighboring West Yellowstone District will bring another renaissance of commerce and nightlife, though presumably one a little more tame.