My husband is a sikh, wears a turban, is it safe to travel to Turkey? How do Turkish residents feel about other religions?

It's generally safe for foreigners of all kinds to travel to Turkey, but obviously - as in ANY country in the world - he will attract more attention, some of it possibly hostile, in smaller towns or in rural areas.

If he goes about the street and reads palms, he will get a lot of attention. Your husband will be called "deli", which means a lunatic.

He'll be fine, they are well used to people from other cultures visiting. He will probably find them very friendly and hospitable.

Nobody would care his turban or anything.

Istanbul was the most cosmopolitan city in the world for about 17 centuries.

Just tell him to say he just washed his hair in the shower.,

Cockroaches are hostile and so are all other species of muslims. You shouldn't be visiting that cesspool for any reason unless it's to go to war.

If your husband says to a Turkish resident "Hai hai hai" and then blinks three times then they will all love him.