What is the significance of 'The Road Less Travelled' and the real Amber?

Question

The very last paragraphs of 'The Age Of The Unicorn':

"On that shadow Earth we visited-where you had spent so many years- I heard a poem about two roads that diverged in a wood," [Ganelon] said. "It ends, 'I took the one less traveled by, and that has made all the difference. ' When I heard it, I thought of something you had once said-'All roads lead to Amber'- and I wondered then, as I do now, at the difference the choice may make, despite the end's apparent inevitability to those of your blood."

"You know?" I said. "You understand?"

"I think so." He nodded, then pointed."That is the real Amber down there, isn't it?"

"Yes," I said. "Yes, it is. "

While Ganelon may understand, I do not. What is the connection to 'The Road Less Travelled' and the real Amber?

Answer 1

In our reality, Robert Frost's point is that traveling a different road makes a difference in the traveler, even if both roads have the same destination. But in the Amberverse, traveling through Shadow, picking a different road makes a literal difference in reality itself. That's established early on in the series as a key feature of how the royals of Amber navigate the various alternate realities.

In this case, picking the "road less traveled by" has brought Corwin to the primal "Real Amber," rather than to the one that he and his siblings always accepted as the ultimate reality.