|This small library in Mecca was built to mark the site of the house where the prophet Mohammed was born: now bulldozed by the Saudis.|
It's not just ISIS, the Saudi Arabians don't care about historic buildings either: a quote from this article in the Guardian (UK) from a couple of years ago.
“The authorities are trying to destroy anything in Mecca that is associated with the prophet's life,” says Irfan al-Alawi, director of the UK-based Islamic Heritage Research Foundation, who recently returned from a trip to the city. “They have already bulldozed the house of his wife, his grandson and his companion – and now they are coming for his birthplace. And for what? Yet more seven-star hotels.”
Nothing of historic Medina or Mecca is said to remain now.