dragon's pool and tiger's den; used to describe a location that is extremely hazardous or an area of hostile territory

Longtan District of [[吉林市|吉林市|ji2 lin2 shi4]] in Jilin province

former administrative township in Taoyuan, Taiwan, currently known as Longtan District

Longtan Ravine, a scenic area in [[西峡县|西峽縣|xi1 xia2 xian4]], [[南阳|南陽|nan2 yang2]], [[河南|河南|he2 nan2]]

tiger's den and dragon's lair; a very hazardous spot or a place where many powerful heroes gather