Gemas (金马士) is a small town in Negeri Sembilan, Malaysia, just near the Negeri Sembilan-Johor state border. The town is located approximately 165 km from the Malaysian capital Kuala Lumpur. It is the meeting place of Malaysian west and east coast rail lines operated by Malayan Railways. For this reason, Gemas is comparatively busy for a town of its size. Gemas railways station was erected in 1922 and is still in operation today.
In addition to the original town center of Gemas, the Johorean side of Gemas is known as Gemas Baharu which is located about 1 km from Gemas town center.
To the southwest stands the famed Gunung Ledang - or its other name, Mount Ophir - with the height of 1276 m.
During the Battle of Malaya in the Second World War, Gemencheh Bridge near Gemas was the site of a fierce battle between the Imperial Japanese Army and the 2/30th Battalion, 8th Division, Australian Imperial Force (AIF). Commanding Officer of the Battalion was Lieutenant Colonel Frederick "Black Jack" Galleghan. Gemencheh Bridge was a bridge over the Kelamah River (Sungai Kelamah in Malay) that connected Gemas with the larger neighboring town of Tampin. The Japanese had passed through Tampin and needed to cross the bridge to reach Gemas.
On 14 January 1942, "B" Company of the 2/30th Battalion, launched an ambush against the Japanese in the hope of preventing them from advancing further south. As the advancing Japanese soldiers passed by the ambush site, the bridge was blown. The battle following the ambush, and a further battle closer to Gemas, lasted two days. It ended with the Australian withdrawal through Gemas to Fort Rose Estate.
Four days later, another encounter between Japanese and Allied soldiers took place near Parit Sulong during the Battle of Malaya. Allied troops, including the Australian 2/19th and 2/29th Battalions, were surrounded and routed there.
A memorial remembering fallen Australians now stands by the site of the destroyed Gemencheh Bridge in Federal route .