In the Persian Empire, people would pour grape-juice concentrate over snow, in a bowl, and eat this as a treat This was done primarily when the weather was hot, using snow saved in the cool-keeping underground chambers known as "yakhchal", or taken from snowfall that remained at the top of mountains by the summer capital — Hagmatana, Ecbatana or Hamedan of today. In 400 BC, the Persians went further and invented a special chilled food, made of rose water and vermicelli, which was served to royalty during summers.[5] The ice was mixed with saffron, fruits, and various other flavours.