Flag of Mongolia
Mongolia is a republic in northeastern Asia, located between the People's Republic of China and Russia.
In the 2007 film prequel comic book "Five to One", Leonardo visits Mongolia during his international pilgrimage, assisting in freeing captured Yeti.
Michelangelo traverse this area tracking down Death Worm at the end of "Lost Years #2". In the next issue, he ends up blinded by radiation poisoning and captured by villagers, who take him in and train him to overcome his blindness before Death Worm's thugs raid the village, slaughtering the villagers and capturing Michelangelo, who recovered his eyesight after being tased.