Isaiah 35 1-10

8 A highway shall be there, and a road, And it shall be called the Highway of Holiness. The unclean shall not pass over it, But it shall be for others. Whoever walks the road, although a fool, Shall not go astray.
Questions
Why would this be a Highway of Holiness?

8 A highway shall be there, and a road, And it shall be called the Highway of Holiness. The unclean shall not pass over it, But it shall be for others. Whoever walks the road, although a fool, Shall not go astray.