Albus Dumbledore was able to do things many other wizards/witches could not. He was after all a brilliant Wizard. The best ever? That's up to the individual to decide. He most certainly (in my opinion) was the most clever - he may even have thought so himself ;).
My question is, How did he detect the "traces of magic" in the Horcrux cave?
References to what I'm asking:
“Yes, this is the place,” said Dumbledore.
“How can you tell?” Harry spoke in a whisper.
“It has known magic,” said Dumbledore simply.
-Harry Potter and the Half-Blood Prince - CH. 26 (The Cave)
Then later on...
Dumbledore approached the wall of the cave and caressed it with his blackened fingertips, murmuring words in a strange tongue that Harry did not understand. Twice Dumbledore walked right around the cave, touching as much of the rough rock as he could, occasionally pausing, running his fingers backward and forward over a particular spot, until finally he stopped, his hand pressed flat against the wall.
“Here,” he said. “We go on through here. The entrance is concealed.”
Harry did not ask how Dumbledore knew. He had never seen a wizard work things out like this, simply by looking and touching; but Harry had long since learned that bangs and smoke were more often the marks of ineptitude than expertise.
-Harry Potter and the Half-Blood Prince - CH. 26 (The Cave)
And mostly importantly...
“How did you know that was there?” Harry asked in astonishment.
“Magic always leaves traces,” said Dumbledore, as the boat hit the bank with a gentle bump, “sometimes very distinctive traces. I taught Tom Riddle. I know his style.”
-Harry Potter and the Half-Blood Prince - CH. 26 (The Cave)
I'm assuming he performed some sort of incantation similar to Homenum Revelio but is there proof of what he did to detect these "traces of magic"?
Did his [Elder] Wand (being as powerful as it is) enable him in any way?
EDIT: I should have clarified that I meant did his Elder Wand help?