In East Anglia, you’ll be able to collect three different Roman Artifacts.
Mercury Temple - Roman Artifact
This artifact is found in Mercury Temple. To get to it, you’ll need to dive under water near the grey female statue, then swim beneath the ruins until you reach a breakable barricade. Break the barricade then swim up to the top of the statue to grab the Roman Artifact. You’ll be swimming for a fair while so be careful not to linger and lose your breath!
Berkelow Bog - Roman Artifact
This artifact is found in Berkelow Bog. Climb to the top of the ruins and jump down into a smaller, enclosed area. On one of the walls, you’ll find the Roman Artifact - climb up the wall to reach it.
East of Theotford Forest - Roman Artifact
This Roman Artifact is located beneath the ruins east of Theotford Forest. You’ll first need to fight off some bandits, then take a fire pot nearby and destroy the barricade in the ground to reveal an underground stairwell. When you reach the end of the passageway, head beneatht the hole in the wall, then shoot the fire pot through the bars to explode the second barricade.