Lóngmén Shān is where the
Yellow River abruptly leaves the vast, rugged expanse of the
Loess Plateau that spreads out in the mountain's north and west to enter a plain which connects both to the nearby
Linfen Basin in the east and to the
Guanzhong Plain further southwest. The mountain is thus a part of the Loess Plateau's southern edge. At the same time, it forms the south-western extreme point of the
Lüliang Mountains, a range that runs parallel to the river as it flows south. The spot at Lóngmén Shān's southwestern tip where the Yellow River breaks through is called Yǔménkǒu (, “
Yu's doorway, or gate”). Here, three bridges span the Yellow River. As there are no other nearby bridges either upstream or downstream, this is the only dry connection from
Xiangning County and
Hejin (in Shanxi province) across the river to
Hancheng (in
Shaanxi province), hence the name
Xiang-Han Yellow River Bridge(s) (). From Yǔménkǒu, Lóngmén Shān stretches in a straight northeasterly direction and then slightly bends eastward toward its opposite end, where a ravine () breaks through to the plain, separating Lóngmén Shān from the rest of the Lüliang Mountains. ==Administration==