When the Spaniards were conquering the Incan empire, the Incans cut off access to the city and gathered in a city to the north to fight. They destroyed the Incan trail that led to the city and so remained hidden for 400 years. 
When the Spaniards were conquering the Incan empire, the Incans cut off access to the city and gathered in a city to the north to fight. They destroyed the Incan trail that led to the city and so remained hidden for 400 years.