This PDF contains a short history of the Longmen lineage, to which many masters of Neidan (Taoist Internal Alchemy) are affiliated. It presents the main stages of development of Longmen, and briefly describes its main branches and masters.
The article is translated from the chapter "Longmen pai" 龙门派 (The Longmen Lineage) in Zhongguo daojiao 中国道教 (Chinese Taoism), ed. by Qing Xitai 卿希泰 (4 vols; Chengdu: Sichuan renmin chubanshe, 1994), vol. 1.