The $7.2 million check used to pay for Alaska (Source: Wikipedia)
In March 1867, the Russian Empire sold Russian America, the territory that would later become the State of Alaska, to the US Government for $7.2 million or about 1.9¢ per acre.
Tsar Alexander II was fearful that he was going to lose the Alaskan territory (including the Aleutian islands) to the British in a future conflict. The colony was never profitable anyway, so he told the Russian minister to the United States to negotiate the sale.
Secretary of State William Seward sealed the deal and was promptly derided for spending so much money on a land so far away. Newspapers labelled the deal "Seward's folly", "Seward's icebox", "Andrew Johnson's polar bear garden", and our favorite: "icebergia."
In 1890s, gold was discovered in Alaska, and in 1968, oil, so Seward
had the last laugh. Today, the last monday of March is celebrated in Alaska as "Seward's Day."