Ma On Shan (peak)

Ma On Shan (; literally: Horse Saddle Peak) is a saddle shaped peak in east of Tolo Harbour in the New Territories of Hong Kong. With a height of 702 metres (2,303 ft), it stands among the ten highest mountains in Hong Kong. The mountain borders Sha Tin and Tai Po districts. Beneath the west face of the mountain along Tolo Harbour, the Ma On Shan new town extension, administratively part of Sha Tin, is named after the hill. It ends north in Wu Kai Sha.

Ma On Shan can be distinguished by the west face which looks like a saddle, and "Ma On Shan" can be translated as "horse saddle mountain". Nine streams flow down from Ma On Shan, with the biggest located on the southwest slope of Ma On Shan, near Ma On Shan Village. A group of villages located east of the peak is named Shap Sze Heung and the harbour of Three Fathoms Cove.

The saddle like peaks of Ma On Shan is formed by volcanic rocks, much like many of the tallest mountains in Hong Kong, such as Tai Mo Shan. The base of the mountain is mostly formed by sedimentary rocks around 120 60 million years ago. The southeastern part of the mountain consists of intruded rhyolite. Some shorter mountains in Hong Kong are formed by older Granitic rocks.

The saddle shape of Ma On Shan was formed over the past 200 million years. Originally, Ma On Shan was a surface of sedimentary rocks covers by volcanic rocks (mainly tuffs) from volcanic eruptions (about 160 mya). The sedimentary and volcanic rocks were then folded into ridges (about 120 mya). Rhyolite rocks intruded the ridge later (about 100 mya). The faulting in the ridges then lead to a more saddle like shape (about 60 mya). The weathering process made the ridges and peaks smooth (about 60 mya now).

In the 1850s, the Wans, a Hakka family, established the Ma On Shan Village. They lived traditional lives of farming. Once iron mining became prominent on the mountain in the 1950s, the villagers slowly transitioned to make a living through mining. As farming was no longer necessary in Hong Kong at the time, these villages were abandoned one by one. During this peak in the mining of iron, most of the miners lived in Ma On Shan New Village. An extensive network of tunnels was built under the hill. However, in the 1970s, Japan’s demand for iron was reduced massively due to them building oil tankers. Therefore, the mining operations in Ma On Shan became unprofitable and uncompetitive. The iron mines were abandoned in 1976. Until 2006, there are still 30,000 tonnes of iron ore in Ma On Shan.