Are caused by earth's internal heat sources.

The answer is - geysers.

The geysers are a natural occurrence that can be found near a geologically active area, where there's a volcano is close proximity. They are in essence a hole that goes deep into the ground, and from it, hot water is shoot upwards towards the surface.

The water is hot because of the heat from the internal heat sources of the Earth. Even though the temperatures bellow are very high, and the water should be in the form of gas, water vapor, because of the immense pressure, it manages to stay in liquid form, and thus gets to the surface as scorching hot water.  

The geysers are very often a tourist attraction, and the best known and most visited are found in the Yellowstone National Park in the northwestern part of the United States.

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