Cape Eluanbi occupies a specific geopolitical position as well as a geographic one. Under current international convention, the boundary between the East China Sea and the Philippine Sea runs through this point. Proposals for a revised edition of the IHO's Limits of Oceans and Seas would also make Eluanbi part of the northern boundary of the South China Sea. The cape marks the southern tip of the Hengchun Peninsula, the long finger of land that extends from Taiwan's Central Mountain Range toward the Philippines. Its underlying geology is a Pleistocene stratum of yellow and brown sand, gravel, and clay — old material, pressed and layered over thousands of years. Archaeologists have found evidence of human habitation here dating to around 3100 BC, which means people were watching these waters from this point five millennia before anyone thought to build a lighthouse.

Shipwrecks were the problem. The Qixingyan reefs and strong currents made the waters off the cape treacherous, and in the 19th century the wrecks of foreign vessels led to confrontations with indigenous Paiwan communities — confrontations serious enough to prompt American and Japanese military expeditions in 1867 and 1874. The lighthouse became an urgent political project. British diplomat Robert Hart, inspector general of the Imperial Maritime Customs Service, sent agents to purchase the cape in 1875. Construction was overseen by Wang Fulu, with 500 soldiers providing protection; the site was defended with 18-pound cannons, Gatling guns, and a mortar, and provisions were stored for three weeks in case of siege. The lighthouse entered service in 1883. The total cost came to 71,248 Mexican dollars. It was not a lighthouse that expected peace.

The Qing structure was damaged in the First Sino-Japanese War, with retreating Qing forces attempting to demolish it themselves. The Japanese repaired it in 1898 and elevated it into a cultural symbol — one of the Eight Views of Taiwan, popularized in travel literature and eventually commemorated in stone calligraphy rendered in the style of Wang Xizhi. During the Japanese occupation, the cape became a major whaling station targeting humpback whales in Banana and South Bays. A Shinto shrine was built on the grounds, one of only five in the world to use baleen whale jawbones as torii gates. Allied bombing during World War II seriously damaged the lighthouse again and destroyed the shrine. The Nationalist government rebuilt the lighthouse in 1947. Eluanbi Park opened on 25 December 1982; the lighthouse itself opened to regular visitors in 1992.

More than 300,000 people visited Cape Eluanbi annually by 2014, many drawn by the southernmost-point marker and the sweeping coastal views. But the cape's biodiversity is its less-advertised distinction. The seas no longer hold the humpback whales that the Japanese whaling industry once targeted here; those populations are gone. What remains is a richly stocked marine environment: dolphins, sea turtles, and bull sharks inhabit the waters. On land, 26 species of terrestrial crabs have been documented at the cape, giving it the distinction of being the most biologically diverse location for land crabs in the world. The Longkeng nature reserve, around Banana Bay, protects coral reefs and old-growth forest. The cape is a place where superlatives — southernmost, most diverse — accumulate without anyone needing to embellish them.