Tong Pass, Mountain fortress in Tongguan County, China.

Tong Pass was a fortress on the south bank of the Yellow River where the Wei River joins it, in present-day Tongguan County, Shaanxi. It stood on the slope of Linzhi Plateau, with the river below and the Guanzhong plain behind it. The old town was demolished in the 1950s for the Sanmenxia Dam; a tall white chimney and grey buildings now mark the far bank.

The Eastern Han warlord Cao Cao began building this fortress in 196 AD to control regional transportation routes. Over time it was expanded and reinforced during several dynasties that followed.

The name Tongguan comes from the Shui Jing Zhu: the Yellow River flows south inside the pass and strikes the pass mountain, hence "Tong Pass". The old fortress was demolished in the 1960s for the Sanmenxia Dam; since 2011 a reconstructed scenic area has been built east of the original site, with a Yellow River culture corridor and a Guanzhong folk commercial street.

The site is reachable by the Longhai Railway or G30 highway with regular transportation links from nearby cities. Visitors should prepare for hilly terrain and bring appropriate footwear.

The pass takes its name from the river: the Shuijing zhu records that the Yellow River flowed south inside the pass and struck the pass mountain, hence "Tong Pass". The Wei River joins the Yellow just below the fortress. In 1960 the old pass was demolished for the Sanmenxia Dam, and the Longhai and Tongpu railways and the G30 expressway now run through the corridor.