How precisely is the へ particle to be understood in 「そこへ、…」 when it means "then"?


The sentence in question ([source](http://life.ou.edu/stories/sarukani.html)):

> そこへ、猿がやって来ました。

It is translated as "Then, the monkey approached".

From what I understand, he へ particle normally is used with a verb to imply
it's general direction, a more specific version of に. I don't quite see how
this meaning would apply here.

