The Jinbaoli Trail runs from Qingtiangang to the Jinshan Highway (2申) and is one of the nicest trails I've walked in Yangmingshan. There are also a few interesting hidden sites just off it. It follows an ancient route used by traders on the north coast to reach profitable Taipei markets. It began to be heavily traveled during the Qing Dynasty, and was used regularly up until the 1950's. Porters carried fish, tea, and sulfur along this steep path, which must have been hellish in summer. A wider, more meandering path, built by the Japanese, runs parallel to the trail, overlapping at some points.
The crater is completely bereft of anything living, and the main vent makes a violent noise. A boiling stream of water flows down a canyon in the middle, and the rocks around it steam. It's an arresting sight and I instantly forgot the trouble getting to it. A cluster of rusted pipes are left from sulfur mining operations. It eventually became too expensive to extract here.
I've plotted the route and a few points on the Hidden Taiwan Map and I highly recommend the Jinbaoli Trail. It's easily linked with a trip to Bayan Hot Springs, which wrote about here. To reach the trail for the springs, I walked for about 20 minutes along the 2申 road on a different day.