Come to the depths of Chang 'an and sing with the world. what's the meaning

Unconsciously, I came to Chang 'an Avenue. I couldn't help sighing when I saw the bustling scene in front of me. Come to the depths of Chang 'an and sing with the world. Come to the depths of Chang 'an and sing with the world. It profoundly embodies the beautiful scenery of Chang' an city. I walked onto Chang 'an Avenue unconsciously. I couldn't help sighing when I saw the bustling scene in front of me. Unconsciously, Chang 'an has become so prosperous.