The ice of the icebergs at Diamond Beach in Iceland is 1000 years old

This deep blue iceberg beached at Jökulsárlón Strandur in Iceland shortly before midnight in midsummer. Encircled by calm waves during low tide, his destiny awaits him with the rising waters of the Atlantic Ocean at the next high tide.
These icebergs originate from the glacier lagoon of the tidal influenced proglacial lake Jökulsárlón at the margin of the Vatnajökull ice cap. Due to the density of ice, about 90% of the volume of floating icebergs is below the water surface. As a result, the largest icebergs are trapped at low tide on large boulders that are part of the rock barrier of the ground and terminal moraine walls that dam the Jökulsárlón tidal lake. The narrow channel Jökulsá, which connects the Atlantic Ocean and the glacial lake, reverses its flow direction twice a day. When the sea-level rises with the tide, sea water drains into the lagoon. This causes the grounded icebergs to float free again. They begin to rotate on the lagoon in large circles, visualizing the water flow. As soon as the water level drops again, the Jökulsá channel reverses its current into an outflow that carries a whole armada of icebergs out into the Atlantic Ocean. They are immediately attacked by the waves that crush them into smaller pieces under impressive sounds. Only the largest icebergs survive long enough to beach at low tide along the Jökulsárlón shoreline for a short period of time. This spectacle is repeated twice-daily.
This iceberg is 2.5 m (8 ft) high. Its deep blue color results from the scattering of the blue shortwave light in the densely compressed ice. This ice was formed from snowflakes that fell on the ice cap of Vatnajökull about 1000 years ago. The cracked structure of the ice reveals the immense pressure and tension to which the ice was subjected when it was still part of the glacier. Along these fault zones, the iceberg quickly falls apart in the surf.
Each of the beached icebergs is unique and the scenery is so evanescent that after a few hours the rising tide leaves no trace of these beauties.