Where the right road was wholly lost and gone

I have long known Dorothy Sayers solely as a British mystery writer. Then, a few years ago, I came across a wonderful and erudite essay on her part, The Lost Tools of Learning, which I wrote about here. Now, I come across the fact that she translated Dante's Inferno, and considered that translation to be her greatest literary achievement. The opening lines:

Midway this way of life we're bound upon,
I woke to find myself in a dark wood,
Where the right road was wholly lost and gone.