Arenaria ciliata, the fringed sandwort,[1] is a perennial herb of the family Caryophyllaceae.

A. ciliata is a calcicole occurring in open grassland and on bare rock in mountainous areas.

It is European with an outlying population in Greenland.

It was discovered in Ireland in 1806 growing on Ben Bulben Co. Sligo.

This remains the only known Irish population.