It is a 29-kilometre (18 mi) chain of hills which runs from southwest to northeast between the Caribbean Sea and the Southern Tobago fault system and reaches a maximum height of 572 m (1,877 ft).

[3] The Treaty of Aix-la-Chappelle in 1748 had designated Tobago neutral territory and left it in the hands of its remaining indigenous population, but the return to British control led to a rapid conversion of the island to a plantation economy.

[3] The decision to preserve forests to maintain rainfall was driven by the efforts of Soame Jenyns, a commissioner of the Board of Trade and Member of Parliament.

[7] Main Ridge reaches an elevation of 572 metres (1,877 ft) above sea level[1] at Centre Hill,[2] but lacks any well-defined peaks.

[11] Main Ridge is primarily underlain by the North Coast Schist Group (NCSG), which occupies the northern third of the island of Tobago.

[1] Main Ridge is dominated by lower montane rain forest[15] (according to John Stanley Beard's classification of the vegetation of Tobago).

[7] In Tobago, these forests are characterised by an emergent canopy of Licania biglandulosa and Byrsonima spicata,[7][16] with the palm Euterpe broadwayi more common on exposed ridges and summits.

[9] The site has been designated an Important Bird Area (IBA) by BirdLife International because it supports significant populations of rufous-vented chachalacas, white-tailed sabrewings, copper-rumped hummingbirds and Venezuelan flycatchers.

[21] The white-tailed sabrewing is endemic to north-eastern Venezuela and the Main Ridge; after Hurricane Flora in 1963 the hummingbird was thought to have been extirpated from Tobago, but was rediscovered in 1974.

[2] The Trinidad and Tobago government submitted the Main Ridge Forest Reserve as a tentative listing for a UNESCO World Heritage Site in 2011.

[24] The Main Ridge Forest Reserve plays an important role in the protection of native biodiversity, particularly endemic plant species.