The capital of Idar princely state was located at:

Himmatnagar
Idar
Vadnagar
Palanpur

The correct answer is: Idar.

Idar was a princely state in India, which was ruled by the Jadeja Rajputs. The capital of the state was Idar, which is now a city in Gujarat, India.

Himmatnagar is a city in Gujarat, India. It is the headquarters of Himmatnagar district.

Vadnagar is a city in Gujarat, India. It is the headquarters of Mehsana district.

Palanpur is a city in Gujarat, India. It is the headquarters of Banaskantha district.