．Geographical Environment
The Penghu islands are a group of large flat-topped basalt cuestas rising out of the Taiwan Straits. Hills are gentle, and the average elevation is only 20 meters above sea level. From a distance the islands look like wooden plates floating upside-down in the sea. The topographical relief gradually slopes down from south to north. 
The highest hill on the main island of Penghu is Mt. Tacheng, which rises to 48 meters above sea level. The urban area of Magong is sheltered by the slopes of Mt. Tacheng in Hsingjen Li, by Lion Hill and Taan Hill to the west, and by Hsiaoan Hill by Makung Harbor, and these hills divide Magong Harbor into northern and southern bays. A range of hills extends southwest from Mt. Tacheng to Chimuwu Hill, Kuanyin Hill, and Shamao Hill, which rises to 45 meters above sea level. 
The city's urban areas includes the western half of the main island of Penghu plus inhabited Huching, Tungpan, and Tsetien islands and uninhabited Chiaoyu, Chilungyu, Niumupingyu, Tayangyu, and Haikanyu (Shihkung reef).

．Climate
Penghu has a year-round average temperature of 23.4°C. The coolest month of January has an average temperature of 16.7°C, while the hottest month of July has an average temperature of 28.7°C. Although Penghu is surrounded by the sea, the islands lack much vegetation and the sun heats up the land rapidly in the summertime. As a result, even the gentle south wind doesn’t relieve the parching summer heat much. While winter temperatures in Penghu are similarly to those in the Chiayi area at the same latitude on Taiwan, but the powerful northeast monsoon winds create a wind chill that makes the air feel around 7°C cooler than the actual temperature. Since the Tropic of Cancer passes through Makung's Huching Li, most of the city is in the subtropical zone, but the part of the city to the south of Huching Li is in the tropics.