The great scholar Zafar Hasan once noted that “the worship of Shiva was far more prevalent [in Delhi] than any other deity.”

Indeed almost every Hindu temple - regardless of sectarian affiliation - will usually have a small ‘Shivalaya’ attached.

BUT I believe these are Jain temples. Jainism is another local Indian religion.

Having said that I’m neither a Hindu nor Jain and my knowledge of Indian religions is very limited.