Yilan County is located in the eastern and northern parts of Taiwan, with its county seat in Yilan City. Yilan County is the birthplace of the traditional opera form, Taiwanese opera (Koa-á-hì). Yilan's diverse mountain landscapes are most distinctive at the Qilan Sacred Trees Park, where hundreds of Taiwan's native red cypress and yellow cypress trees, over a thousand years old, are each named after historical figures according to their age. During guided tours, visitors can review history, forming a unique feature of the park. The seabed hot springs around Gueishan Island emit steam year-round, rising to the sea surface, a rare spectacle in the Pacific Ocean. The waters nearby host an impressive number of whales and dolphins; groups of dolphins leap and roll above the surface, resembling a ballet troupe—an experience entirely different from what is seen at marine parks.