With drilling and extracting technology rapidly improving, what was once thought an impossible place to drill has become the 2nd largest oil production area in the United States.

Through the 1st quarter of 2014, data shows that North Dakota has produced 852 Million barrels, with 151 million barrels produced in Montana.

Harold Hamm, Chariman of Continental Resources Inc. (The Bakken's oldest and biggest operator), estimates that there is more than 20 Billion barrels of oil in the rock formations of the Bakken.

Since oil companies started drilling in the Bakken 14 years ago, the technology to get at the oil reserves has improved dramatically. Today, production is close to 1 Million barrels a day.

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While the Bakken formation is the newest area being drilled in North Dakota, this isn't the first milestone for the state. Oil production in North Dakota started back in 1951, and took 38 years to produce the first Billion barrels. At the current production rate, North Dakota is on track to exceed 3 Billion barrels produced in the state by the end of 2014.