Mecca is the Temple of Mahadev

There is evidence in Sikhism's book

Bhai Wale Wali Janam Sakhi

Sakhi Madine Ki Chali

Hindi Langage - Page 262,

Shri Nanak ji, while answering the question of the four Imams, has said: -

Aakhe Nanak Shah sachch, sun ho chaar imam |
Macca hai Mahadev ka, Brahman san Sultan ||

Meaning: - Satguru Nanak Dev Ji, while discussing with the four Imams, said that Kaaba (temple) in the city of Mecca, which you consider your holy place, is the temple of Mahadev (Shiv ji). There were idols of all the gods and goddesses in it. The sultan (king) who founded it was a Brahmin. Later, all the idols were lifted. It was rebuilt by Prophet Ibrahim and Hazrat Ismail (Alaihi.).