Aksamitova brána, Natural arch in Český kras, Czech Republic.

Aksamitova brána is a limestone rock arch on Kotýz hill in the Zlatý kůň massif, the largest natural gate in Český kras. The preserved opening measures 6 by 4.5 by 2.5 metres, and the open space with vertical walls and no ceiling spans roughly 10 by 13 metres. It likely formed when a large cave ceiling collapsed, leaving the 16-metre-deep Ve Vratech cave below.

The arch formed when the ceiling of a large cave collapsed, leaving a 16-metre-deep abyss called Ve Vratech at its base. Archaeological excavations in the cave ran from 1834 to 1986, and the site is listed as an important archaeological locality together with the nearby Děravá jeskyně.

The arch is named after Jan Axamit, a physician and archaeologist who took part in research in this part of Český kras in the 1920s. Earlier names recorded for the spot were Zlatá vrata, Zlatá díra and the cave Ve Vratech.

The arch lies on Kotýz hill in the Zlatý kůň massif, about 1 km west of the Koněpruské caves in the Tmaň municipality, within the Kotýz national natural monument. The opening measures roughly 10 by 13 metres, and the 16-metre Ve Vratech abyss drops from its floor, so watch your step at the edge.

Excavations in the arch's cave ran from 1834 to 1986, and the 16-metre Ve Vratech shaft at its floor is listed with the nearby Děravá jeskyně as an important archaeological site. The arch was long called Zlatá vrata (Golden Gate) before receiving Jan Axamit's name.