The eastern part of the locality is lower flatter land mostly cleared for irrigated seasonal horticulture. The western part of the locality is hillier and has more natural bushland; it is predominantly used for grazing on native vegetation.[3]
In the 2016 census, Glen Cairn had a population of 113 people.[8]
In the 2021 census, Glen Cairn had a population of 141 people.[1]
Education
There are no schools in Glen Cairn. The nearest government primary schools are Forest Hill State School in neighbouring Forest Hill to the north-east, Blenheim State School in neighbouring Blenheim to the south, and Gatton State School in neighbouring Gatton to the north-west. The nearest government secondary schools are Laidley State High School in Laidley to the east and Lockyer District State High School in Gatton to the north-west.[3]
^"STATE SCHOOL IMPROVEMENT". Queensland Times. Vol. LXVI, no. 12, 340. Queensland, Australia. 1 February 1926. p. 4 (DAILY). Archived from the original on 7 June 2022. Retrieved 6 June 2022 – via National Library of Australia.