1. Gullfoss Waterfall is one of Iceland’s most popular attractions and is located on the Hvítá river in southwest Iceland. The waterfall drops 32 meters into a canyon, and on sunny days, a bright rainbow can be seen over the falls. The name \"Golden Falls\" comes from the golden hue of the water in the sunlight. Interestingly, the waterfall was almost destroyed in the early 20th century when a proposal was made to dam the river for hydroelectric power. However, the owner’s daughter fought against it by threatening to throw herself into the falls, and the area was eventually protected as a national park.

2. The waterfall is open to visitors year-round, but the hours of operation vary depending on the season. From May 1st to September 30th, the waterfall is open from 9:00 AM to 7:00 PM. From October 1st to April 30th, the waterfall is open from 10:00 AM to 4:00 PM. Unfortunately, there is no phone number available for Gullfoss Waterfall.

3. There is no admission fee for visiting Gullfoss Waterfall, so visitors are free to explore at their leisure. However, there is a parking fee of 600 ISK (approximately $4.50 USD) for cars, and 200 ISK (approximately $1.50 USD) for motorcycles. The easiest way to reach the waterfall is by car, which takes approximately 1.5 hours from Reykjavik. Alternatively, visitors can take a tour bus or arrange for a private transfer.