Saints Julius and Aaron were two more British martyrs who died probably in the amphitheatre at Caerleon in South Wales, under the Emperor Diocletian in 304. There were 2 chapels some two miles apart, one for each of the saints, perhaps reflecting the place of their executions. They were obliterated at the Reformation.
The 6 century writer Gildas adds that there were other martyrs of both sexes in different places.
Troparion Tone 4
O holy martyrs, bright lights of Wales,
you gave up your life at Caerleon.
The crowd may have roared in the amphitheatre,
but your eyes were fixed on your welcome in heaven.
O Holy Julius and Aaron, pray for us!
