What does "to track five" mean in English for Spanish?

In English for Spanish, "to track five" means:

al andén 5

Listen to "to track five": (If you have an HTML5 enabled browser, you can listen to the native audio below)

This is a phrase that is used in the GamesForLanguage English for Spanish Language Game in the following scenes:

• English for Spanish 3, Level 3, Scene 9