the narrator says there were a couple of places now which i wanted to see. both were fearful sites and that is why i wanted to see them. what are the two fearful sites

The tree by the river and the marble staircase.

Explanation:

From the book "A Separate Peace by John Knowles"

The tree by the river and the marble staircase hold bad memories for him. The tree is the place from which Phineas fell, as an adult he sees it is weary from age, enfeebled, dry. Because of this, he comes to understand that, Nothing endures, not a tree, not love, not even a death by violence.