Over the past one hundred years, a national network of vertical control points or "benchmarks" has been created by levelling along major roads and railways in Canada and by linking more than 30 tide gauges operated by the Fisheries and Oceans Canada.

Benchmarks are spaced at approximately 2-km intervals along major highways and railways.

While vertical control may be established by many different methods, the primary vertical control network is established using differential levelling only.