"The Bridge"

I really like this song, "The Bridge", from the CD "The Captain and The Kid", by Elton John. What does the "bridge" symbolize?
Courage? Faith? Risk? Death? The future?
Here are the lyrics to this song that some critics are calling "Elton John's best in years."
What do you think "The Bridge" symbolizes?
You can listen to the song at AOL by clicking here.

I've seen the bridge and the bridge is long
And they built it high and they built it strong
Strong enough to hold the weight of time
Long enough to leave some of us behind

chorus: And every one of us has to face that day
Do you cross the bridge or do you fade away
And every one of us that ever came to play
Has to cross the bridge or fade away

Standing on the bridge looking at the waves
Seen so many jump, never seen one saved
On a distant beach your song can die
On a bitter wind, on a cruel tide [repeat chorus]

And the bridge it shines
Oh cold hard iron
Saying come and risk it all
Or die trying [repeat chorus]