A large iceberg on Iceland’s Diamond Beach in midsummer

The beached icebergs at Jökulsárlón Strandur on Iceland are the remnants of the Vatnajökull ice cap and its southern glacier lobe Breiðamerkurjökull, which ends in the proglacial lake of Jökulsárlón. The lake extends for approx. 20 km (12.4 mi) beneath the eastern part of the glacier, which partially floats up. The lagoon of Jökulsárlón is filled with icebergs that calve continuously from the glacier front. The glacier lagoon is located at sea-level and connects with the open ocean of the North Atlantic through the 500 m (1600 ft) long river channel, the Jökulsá. The river cuts through the glacier terminal moraines that dam up the lake.
This channel has been forming during sporadic deluge-like meltwater outbursts, the Jökulhlaups, which occur when volcanoes erupt underneath the ice of the Vatnajökull ice cap and melt the ice abruptly. During the high tide, the salty sea water flows through the channel into the lagoon at high speed, which significantly increases the lake level.
With the onset of low tide, the brackish lake water flows back through the channel into the ocean and carries icebergs up to 5 m (16 ft) height out into the Atlantic Ocean. These icebergs are immediately exposed to the powerful surf. The waves break the icebergs into smaller pieces under impressive sounds. At low tide, the remnants of these icebergs beach on the black lava sand. The scenery is reminiscent of a bone yard of crystal debris. This iceberg excels with a spectacular hole through which the distant volcanoes can be seen. For a few hours this beautiful iceberg of 1.5 m (5 ft) height rested on the beach in midsummer at dusk around midnight, before it was destroyed forever by the Atlantic surf.