Engravings thought to be about 10,000 years old have been found in a North Somerset cave once used as a cemetery.
The engravings were found in a cemetery
Bristol University's Speleological Society discovered the engravings recently in a cave in the Mendip Hills.
The inscribed crosses were found on the wall of Aveline's Hole in Burrington Combe, one of the earliest known cemeteries in the UK.
It was used for burials shortly after the end of the last ice age, during the early Mesolithic period.
Jill Cook, from the British Museum, said: "This is an exciting and important discovery.
"The few lines that form this panel are a signature from the period right at the end of the last ice age when the present period of warm climate was beginning.
"The pattern is comparable with others known from Northern France, Germany and Denmark."
The engravings were identified by Graham Mullan and Linda Wilson, who have spent much of the last 10 years studying Palaeolithic cave art.
They recently began a systematic search of caves in southern Britain in the belief that such works would not simply be confined to those found at Creswell Crags, on the Nottinghamshire-Derbyshire border.
The Creswell features are a little older at about 13,000 years and were first detailed by scientists in 2003.
Aveline's Hole was used for burials
They depict representations of bison, deer, bears, plus two or three species of bird; including one unusual bird head with a long, curved bill.
Mullan and Wilson are continuing their search of southern Britain and believe more works like those at Aveline's Hole will surface.
A further engraving has been noted in one of the caves in the Cheddar Gorge, and further investigations are being carried out to verify this.
However, for the vast majority of engravings, it is impossible to obtain any direct dating evidence, leaving stylistic comparisons and archaeological context the only means of reaching a conclusion on the possible age of any such markings.