The andesitic-dacitic younger Tolima formed during the past 40,000 years, rising above and largely obscuring a 3 kilometres (1.9 mi) wide Late Pleistocene caldera.

The summit consists of a cluster of Late Pleistocene to Holocene lava domes that were associated with thick block-lava flows on the northern and eastern flanks, and extensive pyroclastic-flow deposits.

[1] The snow-capped Nevado del Tolima, with its almost symmetrical structure, has a radial drainage pattern in the upper part.

The residual glacier on the top of the mountain feeds the rivers Totare, San Romualdo, Toche and Combeima.

The park is administratively part of the municipalities Villamaría, Santa Rosa de Cabal, Pereira, Salento, and Ibagué.