Old Faithful is a cone geyser located in Yellowstone National Park, Wyoming, United States.
An eruption can shoot 3,700–8,400 gallons (14,000–32,000 l) of boiling water to a height of 106–184 feet (30–55 m) lasting from 1.5–5 minutes. The average height of an eruption is 145 feet (44 m). The intervals range from 65–92 minutes with 91 minutes being the average.

This has been a challenging shot for me. I had to wait and hope for the magic moment when the Sun was just disappearing behind the mountain and the geyer was just erupting at its peak height. Although the eruption was 10 minutes later than the estimated time, it happened just in time before the Sun finally disappeared. I did not have my tripod with me so I had to handhold and shoot at a high ISO of 1600, maximum aperture and 1/20 second shutter speed.

Hope this image brings you the beauty of our planet and inspire us to preserve it. Thanks.

Footnote: another memorable component of this image was that after shooting this image at 9:00 p.m. (I did not update time zone change on the clock of my camera), I still had to drive 3 hours in pitch black back country road to get to my next hotel in Livingston. After a long day of activities I was already exhausted, the driving was like hell.