Why is the little town empty in these lines from verse IV of "Ode on a Grecian Urn" by John Keats?

• ItsJustLuly: In the fourth stanza of his poem 'Ode on a Grecian Urn', John Keats describes the little town as empty; the streets are 'silent' and it is 'desolate' of people.
  Every single person who lives in the town is heading to a sacrifice since it is a holy day, but no one is left in town to inform the protagonist of this. 
• perlagarcia8121:

  Read the excerpt.

  
  

  Who are these coming to the sacrifice?

  To what green altar, O mysterious priest,

  Lead’st thou that heifer lowing at the skies,

  And all her silken flanks with garlands dressed?

  What little town by river or seashore,

  Or mountain-built with peaceful citadel,

  Is emptied of this folk, this pious morn?

  
  

  Why is the little town empty in these lines from Verse IV of “Ode on a Grecian Urn” by John Keats?

  
  

  The people are all farmers who are tending their cattle in the fields.

  
  

   

  The people were sacrificed by priests of conquering armies.

  
  

   

  The people have all gone to attend a religious ceremony.

  
  

   

  The people have all gone on trips to the seashore or mountains.