The pair joined the club full-time in July 1997 and their careers pretty much ran parallel for a good while, with both getting a run in the first team following the home victory over Liverpool in November 2000.
Alton suffered with injury problems for most of last term and has now departed for Hull City where he hopes to kick-start his career in the Nationwide League. For Ledley though, it won't quite be the same.
"Definitely. He's a good player and I've been playing with him since we were 15," he reflected.
"Obviously I'm sad to see him go. He was unlucky, especially last season, as he was injured for most of it.
"He is at Hull at the moment and he will do well there. I'm sure he will bounce back through the leagues."
Seasoned professionals become immune to the comings and goings at football clubs and Ledley is now the last of his Academy side still at Spurs.
"It's true. When you are 16 everyone with you is the same age - there is no one left now from my group which is disappointing.
"Gavin Kelly, who has just left, is the same age. That's football though and hopefully I can fly the flag here for them."
Ledley King admits that life at the Lane will be a little strange for a while without his friend on long-time teammate Alton Thelwell.