Question

hwsat is the significance of hadrians wall

Answer 1

The Romans were doing a pretty good job of conquering the Britannia. When they got to what is now Scotland, they encountered the Picts. The Picts didn't like the idea of being conquered. They knew their home land pretty well and gave the Romans fits.
The Roman army was extended a long way from Rome and decided Scotland wasn't worth all the trouble.
Hadrian built a wall across a narrow part of the island and left troops to guard it. That kept the Picts on the North and allowed Roman armies to go conquer other place.