In 1900 Filchner crossed the Pamirs, the mountainous region of central Asia now chiefly within Tajikistan, and he made an expedition to Tibet in 1903–05. Sailing for Antarctica in the Deutschland (1911), he penetrated the Weddell Sea at 77°50′ S early in 1912 and charted the Luitpold Coast (which he named for the prince regent of Bavaria) between 29° and 37° W. In March the ship became trapped in the pack ice and drifted until it finally became freed at 63°37′ S, 36°34′ W on Nov. 26, 1912. In Tibet again (1926–28), Filchner conducted cartographic surveys and magnetic observations; he also made a magnetic survey of Nepal (1939–40). His writings include Das Rätsel des Matschu (1907; “The Riddle of the Matschu”), Zum sechsten Erdteil (1923; “To the Sixth Continent”), and Ein Forscherleben (1950; “An Explorer's Life”).