Complex sentence: Sitting by the Strait of Magellan Punta Arenas was established originally as a tiny penal colony in 1848 but became during the 19th increasingly large and important as international trade across the straits grew and the countryside around experienced a gold rush and a sheep farming boom around 1900.
Split into simpler sentences: Sitting by the Strait of Magellan Punta Arenas was established originally as a tiny penal colony in 1848. During the rest of the 1800s, it became increasingly large and important as international trade across the straits grew and the countryside around experienced a gold rush and a sheep farming boom around 1900.