The most prominent structure on Dongji Island is its lighthouse, built in 1911 during the period of Japanese colonial rule over Taiwan. The Dongji Island Lighthouse has stood for over a century at the island's highest point, marking the southern approach to the Penghu archipelago for ships navigating the Taiwan Strait. The lighthouse predates the island's inclusion in any national park, its construction reflecting the strategic importance of these waters to Japanese maritime interests. The Strait is shallow here, and the Penghu Islands have always posed navigational hazards. The lighthouse's beacon has guided fishing boats, cargo ships, and ferries through waters that remain commercially active. In January 2018, the cargo ship Chia Ming Lun ran aground near Dongji and sank. The ship and its cargo were never salvaged, a reminder that the strait can still claim vessels despite a century of improved navigation.

Before the lighthouse, there was the temple. A shrine dedicated to Wang Ye worship was built on Dongji Island during the Jiaqing era of the Qing dynasty -- the early nineteenth century -- and restored in 1872. Wang Ye worship, a folk religious tradition focused on plague-averting deities, is widespread across Taiwan's coastal and island communities, and its presence on Dongji speaks to the island's long connection to the broader Fujianese cultural sphere from which most Penghu settlers came. The temple remains the spiritual center of the island's small community. The waters surrounding Dongji tell their own story of vulnerability and conservation. In October 2019, over 800 kilograms of abandoned fishing nets -- ghost nets -- were removed from the coral reef near the island. These discarded nets, left by fishing operations, entangle marine life and damage coral. The cleanup effort reflected growing attention to the ecological fragility of the reefs that Dongji's national park status was meant to protect.

In June 2014, Dongji Island was incorporated into the newly established South Penghu Marine National Park, a designation that recognized the ecological significance of the southern Penghu Islands and their surrounding waters. The park protects coral reefs, marine habitats, and the basalt geological formations characteristic of the Penghu archipelago. Dongji's village sits near the center of the island, in an area that was once underwater -- a geological detail that underscores how much these islands have been shaped by sea-level changes over millennia. The smaller Chutou Islet, once inhabited, lies just to the northwest. The marine area of Taijiang National Park extends 54 kilometers from the Yanshui River to Dongji Island, covering 344 square kilometers. In May 2016, a ferry service between Tainan and Dongji began operation, connecting the island to Taiwan's main island for the first time by regular scheduled transport.

Dongji Island's climate sits at the boundary between tropical and humid subtropical. Being a small island in the shallow Taiwan Strait, it experiences less dramatic temperature swings than either mainland Taiwan or the Asian continent to the west. Winters are dry and mild, with comfortable conditions for outdoor activity despite persistent cloud cover. Summers bring rain as the East Asian monsoon pushes through the high-pressure systems that otherwise dominate the region. The island is sunnier and drier than the Taiwanese mainland -- a quality that, combined with its remoteness and the absence of commercial development, gives Dongji a quality of arrested time. The fishing harbor, the lighthouse, the Wang Ye temple, and the stone houses of the village compose a landscape that has changed little in decades. For the fishermen who still work these waters, the island is a working port. For the trickle of visitors who arrive by ferry, it is something closer to a revelation: Taiwan stripped to basalt, coral, and wind.