LotR -- Book 1 - Chapter 07 - In the House of Tom Bombadil

[Estelyn Telcontar]

When I began to read the next chapter, I glanced at the opposite page, the end of this chapter, and a detail caught my eye. Tom is warning the hobbits against the Barrows and the Wights and:

advised them to pass barrows by on the west-side, if they chanced to stray near one.

I have a vague memory of a discussion on that thought some time back, but don't remember which thread it was. To pick up that question here - why on the west-side? What significance does that advice have? Does it have something to do with Valinor being in the west?

Of course, since it was foggy when they got there, I don't suppose that the hobbits would have known where west was, even if they had seen the barrows...