There are some musallahs or sajjadah that has image of Makka Shafir or Madina Sharif and sometimes both of them. When we go in Sijdah, our knees are on this image. Is this bay-adab and/or sin or is it okay.

There is element of disrespect and one should refrain from it. Such things shouldn’t be around the praying places where there is a picture of the House of Allah or the Prophet’s grave.
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