The world's largest iceberg, A-23A, a 'megaberg' that once spanned 1,540 square miles and weighed nearly a trillion tonnes, has finally disintegrated into small fragments after a nearly 40-year journey. Calved from Antarctica's Filchner Ice Shelf in 1986, it remained grounded for over three decades before beginning its drift in 2020. The iceberg traveled more than 2,000 miles north, eventually reaching the South Atlantic Ocean. In its final months, extensive melting and breakage occurred, significantly reducing its size. A-23A's journey posed a potential threat to the British island of South Georgia, but it ultimately ran aground off its coast in March 2025, where it continued to break apart. Its meltwater also contributed to a phytoplankton bloom, benefiting local marine life.