Hegyestű Hill

The preserved volcano

Hegyestű is the remnants of an ancient volcano’s chimney, eroded from it’s surroundings. From it’s former horn, the magma of basalt composition crashed towards the earth’s surface, stalling and cooling, solidifying into pentagonal and hexagonal basalt columns, 20-40 cm in diameter, and like organ pipes, fold in the direction of the mountain peak. In some places, pepperite rocks can be observed at the edges of the horn, indicating a mixture of magma and pierced rock. At the lower levels, in the so-called “cornstone” basalt, the bladder caverns of former volcanic vapors and gases have settled in. Although the geological display boards report the first eruptions to be blast-blasting, and tuff-rings created around the eruption point as a result, there is no evidence of such a tuff-ring, in the most recent explorations.
Following volcanism, erosion was the next dominant feature of the area. Erosion destroys softer, less resistant rocks and sediments faster, and more resistant harder rocks more slowly. Correspondingly, hard bodies of basalt have evolved over millions of years, from their softer environment, and these basalt bodies represent the typical “witness hills” of the Balaton Uplands.
After the former mine was converted into a conservation area, the neglected area was restored in 1996-97. A permanent exhibition was opened in one of the mining buildings in 1998, showing the former quarry, the natural values of the Balaton Uplands National Park, the history of the Balaton Uplands, as well as the rocks and formations of Hegyestű. At the geological exhibition site, setup in the mining yard, an array of typical rocks of the Káli Basin are on display, along with plaques showing basalt volcanism, and other basalt-related information. On the panoramic table, one can see drawings from the Kossuth Prize winning artist, Győző Somogyi, helping us identify the panoramic elements of the Káli Basin, such as: mountains, lakes, and settlements. In the parking lot, the typical rocks of Transdanubia are represented in an outdoor stone exhibition.