Korean yen
The Korean yen was the currency of Korea between 1910 and 1945. It was equivalent to the Japanese yen and consisted of Japanese currency and banknotes issued specifically for Korea. The yen was subdivided into 100 sen. It replaced the Korean won at par and was replaced by the South Korean won and the North Korean won at par.
Beer in North Korea
Tourists may buy beer with foreign currency without the limitations that apply to North Koreans. Beer in international hotels cost about two euros. Indeed, for tourists, according to Josh Thomas, the actual "price of drinking North Korean beer is bowing to a lot of statues of Kim Il-Sung and Kim Jong-Il, listening to their version of the Korean war, and eating anything and everything they give you to eat".