Both the Statehood and the D.C. & U.S. Territories quarter programs had proven incredibly popular. So Congress authorized the U.S. Mint to issue a new 56-coin series with special reverse designs honoring a national park or historic site in each of the 50 states, the District of Columbia, and five U.S. territories of Puerto Rico, Guam, American Samoa, the U.S. Virgin Islands and the Northern Mariana Islands. Released at the rate of five designs per year 2010-2021, the series continued John Flanagan’s modified Washington portrait obverse design.
