Longwanqun National Forest Park, National forest park and crater lake group in Huinan County, Jilin, China

Longwanqun National Forest Park is a nature reserve in Huinan County, Jilin Province, built around a group of seven volcanic crater lakes. The lakes sit inside forested hills on the western edge of the Changbai Mountains, each one occupying its own crater and differing slightly in size and color.

The area around the crater lakes was designated a national park to protect the mixed forests of Manchuria and the native species that live there. The lakes themselves were formed by ancient volcanic activity tied to the same geological forces that shaped the broader Changbai range.

The lakes are named longwan, "dragon bays", and the six in Huinan County were made a national forest park in 1992, rated a 4A scenic area in 2005 and added to the IUCN Green List of Protected and Conserved Areas in 2015. The group formed from volcanic eruptions between the late Early Pleistocene and early Middle Pleistocene and is the largest cluster of maar lakes found in China.

Trails connect the different crater lakes and are generally easy to follow on foot, making it possible to visit several in a single day. Weather in forested mountain areas can change without warning, so bringing a waterproof layer is a good idea regardless of the season.

Although all seven lakes share the same volcanic origin, their water can appear in noticeably different shades when seen from the shore. This difference comes from variations in depth and mineral content, and it is visible without any equipment simply by walking between the lakes.