Costa Rica Travel News – Formed by the confluence of two smaller rivers, the Rio Celeste is a bright blue river in Costa Rica that winds through the lush rainforest of Tenorio Volcano National Park.
The color is caused by Mie scattering, according to Amusing Planet, a phenomenon caused by the presence of large particles of a mineral called aluminosilicate in the river’s water, which reflect sunlight, giving rise to the vibrant blue hue.
Aluminosilicate is found in the Good View River but the color doesn’t occur in this stream because the particles are too small, reports Amusing Planet. It is only when Good View River mixes with Sour Creek, a stream that has highly acidic water due to volcanic activity, that the color occurs. When the two waters mix, a drop in pH occurs, causing aluminosilicate particles to aggregate and enlarge enough for the Mie scattering phenomenon to occur in Rio Celeste.
There are two trails of varying difficulty that lead to the blue river of Rio Celeste. More experienced hikers can take the moderately challenging 4.5 mile-long trail through the rainforest, past thermal hot springs and a blue lagoon; while visitors can venture along the shorter (one mile) path from the park entrance directly to the Rio Celeste Waterfall.
By Simone M. Scully, weather.com