Southbrook is in the Mandeville riding of the county of Ashley. It is built on the Christchurch-Culverden line, nineteen miles from Christchurch, and a little more than one mile from Rangiora. The railway station stands at an elevation of fifty-five feet above the sea. There are two flour mills, a flax mill, a number of churches, a public school, post office, and two stores in the district, which was formerly covered with heavy bush. This, however, has all been cleared away, and the land is now covered with agricultural and dairy farms. At the census of 1901 Southbrook and neighbourhood had a population of 1070 souls.