Gullfoss is the waterfall that sums up Iceland: a huge volume of glacial water from the Hvítá river dropping in two steps into a narrow canyon, with spray hanging in the air and rainbows appearing on sunny days. The upper fall is wide and the lower one plunges into a crevice at right angles, so the water seems to vanish into the earth, and the noise is a constant, low roar that you feel in your chest.
The ride here is easy and pleasant. The road crosses open upland, with the Langjökull glacier on the horizon and the river winding through the valley, and the bends are gentle. The surface is generally good, but wind and rain can come in suddenly, and in winter ice and snow close or restrict the road. The car park is a short walk from the falls, and the paths can be wet and slippery from the spray.
The falls were once threatened with a hydroelectric scheme, and local legend says that Sigríður Tómasdóttir, the daughter of the farmer who owned the land, walked to Reykjavík and threatened to throw herself into the water if the plan went ahead. The details of the story are partly folklore, but the falls were eventually protected. It is a nice tale about how a country decided what it valued.
The nature around the falls is bleak and beautiful. Low scrub, moss and grasses cover the plain, and the canyon walls are streaked with mineral colours. The mist from the falls supports a surprising amount of life, and in summer the air smells of wet stone and fresh water. The glacier river brings milky grey water from the ice cap to the north.
From here the Kjölur highland road heads north into the interior, a gravel route for those with the right bike and the right season. Services at the falls include a visitor centre with food and shops, so you can usually get a hot meal. Go in the morning, when the sun lights the spray, and wear warm and waterproof clothing.