And now there are two.
Washington is now selling recreational marijuana.
At least on a smaller scale compared to Colorado.
"We anticipate a crowd around the block," said Aaron Nelson, Vice President of 20/20 in Washington state. He told KOMO-TV in Seattle, "We're ready to go."
Pot legalization is seen by some as a sign of the times.
While the two states legally allow it, those laws are different
Growing pot plants at home is not allowed at all in Washington, but in Colorado, it is, at least in small quantities.
Medical marijuana is allowed statewide in Colorado, while cities must individually vote to legalize recreational use.
In Washington - medical marijuana was illegal.
And the evergreen state is slowly implementing the law, only allowing 24 licenses to start shop.
That's a mistake according to one Colorado springs club owner.
"The law of supply and demand is going to continue to push the numbers," said Robert Tillery, Organizing Director of Club 710.
He equates his club to any other social organization.
"Like a book club, a car club, but we're a cannabis club," Tillery said. "We're cannabis enthusiasts who meet and exchange information."
Originally there was a rush on the novelty, now he says business fluctuates depending on supply and demand.
Out-of-towners are a big part of the business.
"Cannabis tourism. We've had travelers who said they made the club their destination, and they plan to visit Cave of the Winds, Pike's Peak.
With millions pouring into the state in tax revenue, other states are likely to take a second look at lighting up.
Voters in Alaska, Florida and the District of Columbia will decide in the November election if pot should be legal.