* Astronomy

Hiiumaa, Estonia's second largest island, is said to have been created 455m years ago by a meteorite strike.

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The buried and well preserved Kärdla crater in Estonia (Southern Fennoscandia) (58°59'N, 22°40'E), with a diameter of approximately 4 km, was discovered in 1967. The subsurface structure of the crater has been studied by gravity anomaly measurements, aeromagnetics and by more than 300 boreholes in the crater, on the rim (ring wall) and in the surrounding area. Recent boreholes, reaching 800 m, have revealed that the crater is 540 m deep and has 100 m high central peak. Barely visible in the present topography, the crater is filled with Palaeozoic and Quaternary deposits and is mostly low marshy land surrounded by a low ridge along the ring wall.

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