He is from the northern border city of `Ar`ar and is asking about his miqat for Hajj and `umrah
Question

I live in the northern border region of Saudi, to be precise in the city of `Ar`ar, and I am going to do Hajj this year, in sha Allah, with a group. I want to ask what is the miqat at which I must enter ihram for Hajj and `umrah?
Praise be to Allah.For those who live in the north, in the direction of Iraq, such as the people of the northern border region (`Ar`ar), the basic principle is that their miqat is the miqat of the people of Iraq. The miqat of the people of Iraq is Dhat `Irq, as Abu Dawud (1739) narrated from `A’ishah (may Allah be pleased with her) that the Messenger of Allah (blessings and peace of Allah be upon him) defined the miqat of the people of Iraq as Dhat `Irq. Shaykh al-Albani classed this report as authentic in Sahih Sunan Abi Dawud.
But because the road to Dhat `Irq is currently unpaved and unused, people from that direction started to enter ihram from Dhu’l-Hulayfah, which is the miqat of the people of Madinah. Some of them travel by way of Riyadh, so they enter ihram from the miqat of the people of Najd, which is Qarn al-Manazil (as-Sayl al-Kabir).
Based on that, if your route to Makkah is via Madinah, then you should enter ihram at the miqat of the people of Madinah, i.e., Dhu’l-Hulayfah.
But if  you come via Riyadh, then you should enter ihram at Qarn al-Manazil (as-Sayl al-Kabir), because al-Bukhari, 1525, and Muslim, 1181, narrated that Ibn ‘Abbas (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) defined the miqat of the people of Madinah as Dhul-Hulayfah; that of the people of Sham (Greater Syria) as al-Juhfah; that of the people of Najd as Qarn al-Manazil; and that of the people of Yemen as Yalamlam. And he said: “And these miqats are for the people at those very places, and besides them for those who come through those places with the intention of performing Hajj and ‘Umrah; and whoever is living within these boundaries can enter ihram from the place he starts, and the people of Makkah can enter ihram from Makkah.”
And Allah knows best.