Firstly:
Regarding the current location of Hell, there is no sound proven text of the type that may be taken as evidence regarding such matters of the unseen. Hence the scholars differed regarding it. Some of them said that it is in the seventh earth, as is the well-known view, some of them said that it is in the heavens, and some of them were uncertain about the matter, because there is no proven definitive text that leaves no doubt about this matter.
In Al-Mawsu`at al-`Aqadiyyah – from Aldorar Alsaniyyah – it says
Regarding Hell – may Allah protect us from it – the scholars have stated that it is in the seventh earth, or that we cannot identify its location. It also says in Al-Mawsu`at al-`Aqadiyyah: As for its location, Ibn `Abbas (may Allah be pleased with him) said: Hell is in the seventh earth. Narrated by Abu Na`im.
Ibn Mandah narrated that Mujahid said: I said to Ibn `Abbas (may Allah be pleased with him): Where is Hell? He said: Beneath seven seas, one above the other…
Ibn Khuzaymah and Ibn Abid-Dunya narrated from `Abdullah ibn Salam (may Allah be pleased with him) that: Paradise is in the heavens and Hell is on earth. Ibn Abid-Dunya narrated from Qatadah: They used to say that Paradise is in the seven heavens and that Hell is in the seven earths. In the hadith of al-Bara’ about the disbeliever it says: “Allah will say: ‘Place his record in Sijjin (the lowest Hell) in the lowest earth,’ then his soul will be thrown there.” It was narrated by Imam Ahmad and others.
Imam Ahmad narrated, with an isnad concerning which there are some reservations, from Ya`la ibn Umayyah, that the Prophet (blessings and peace of Allah be upon him) said: “The sea is Hell.” They said to Ya`la: Do you not sail on the sea? He said: Do you not see that Allah says: {For the wrongdoers We have prepared a fire which will encompass them like the walls of a pavilion} [al-Kahf 18:29]? No, by the One in Whose Hand is the soul of Ya`la, I will never sail on the sea until I meet Allah, may He be Glorified and Exalted, and no drop of it should touch me until I meet Allah, may He be Glorified and Exalted.
Al-Hafiz Ibn Rajab said: What this means – if it is proven to be soundly narrated – is that the seas will burst forth on the Day of Resurrection and will become one sea, then fuel will be added to it and lit, and it will become fire which will be part of the fire of Hell. And he interpreted the verse {And when the seas are filled with flames} [at-Takwir 81:6] in a similar manner. Ibn `Abbas said: {filled with flames} means: it will become fire. According to a report narrated from him: The sun, moon and stars will be in the sea, then Allah will send upon it a strong wind which will blow onto it until it turns into fire. This was narrated by Ibn Abid-Dunya and Ibn Abi Hatim. And they narrated from him regarding the verse {verily Hell will encompass the disbelievers} [al-`Ankabut 29:54] that he said: This refers to the sea; the heavenly bodies will be thrown into this sea, and the sun and moon will be wrapped up [in darkness] and be thrown into it.
Sayyiduna `Ali (may Allah be pleased with him) said to a Jewish man: Where is Hell? He said: Beneath the sea. `Ali said: He is right. Then he recited the verse {And when the seas are filled with flames} [at-Takwir 81:6]. Narrated by Ibn Abi Iyas.
Ibn Abi Hatim narrated from Ubayy ibn Ka`b that he said regarding the verse {And when the seas are filled with flames} [at-Takwir 81:6]: The jinn said to humankind: We will bring you some news. Then they went to the sea and found it raging with fire.
In Sunan Abi Dawud it is narrated from Ibn `Amr in a marfu` report [attributed to the Prophet (blessings and peace of Allah be upon him)]: “No one should sail on the sea except a pilgrim who is going to do Hajj or `umrah, or one who is fighting in Allah’s cause, for beneath the sea there is a fire, and beneath the fire there is a sea.”
It was narrated from Ibn `Umar in a marfu` report [attributed to the Prophet (blessings and peace of Allah be upon him)]: “Hell is surrounded by this world, and Paradise is beyond it, hence the sirat (bridge) over Hell is a path to Paradise.” Al-Hafiz Ibn Rajab said: This is an odd gharib hadith.
And it was said that Hell is in the heavens. Imam Ahmad narrated from Hudhayfah (may Allah be pleased with him), that the Prophet (blessings and peace of Allah be upon him) said: “Al-Buraq was brought to me, and Jibril and I did not dismount until I was brought to Bayt al-Maqdis [Jerusalem] and the gates of heaven were opened to me, and I saw Paradise and Hell.”
It was also narrated from him that the Prophet (blessings and peace of Allah be upon him) said: On the night on which I was taken on the Night Journey, I saw Paradise and Hell in the heavens, and I recited this verse: {And in the heaven is your provision and whatever you are promised} [adh-Dhariyat 51:22], and it was as if I had never recited it before.”
However, there is no proof in this and similar reports that Hell is in the heavens, because it is possible that he saw it on earth when he was in the heavens. The deceased sees Paradise and Hell when he is in his grave, and Paradise is not on earth. And it is soundly narrated that the Prophet (blessings and peace of Allah be upon him) saw them both when he was offering the eclipse prayer, at which time he was on earth. According to some narrations of the hadith of the Night Journey from Abu Hurayrah, the Prophet (blessings and peace of Allah be upon him) passed by the locations of Paradise and Hell on his way to Bayt al-Maqdis. But none of these reports indicate that Paradise is on earth. The hadith of Hudhayfah – if it is authentic – says that he saw Paradise and Hell in the heaven, so the heaven is the place from which he saw them, not the location of what he saw. In other words, what he meant is: I saw Paradise and Hell when I was in the heavens. The hadith does not refer to the location of the things seen, so think about that.
End quote from Al-Buhur az-Zakhirah fi `Ulum al-Akhirah by Muhammad ibn Ahmad as-Safarini, 3/1313.
It was narrated that `Abdullah ibn Salam said: The most noble of Allah’s creation is Abul-Qasim (blessings and peace of Allah be upon him), and Paradise is in the heavens. Narrated by Abu Na`im.
He also narrated from Ibn `Abbas that Paradise is in the seventh heaven, and Allah, may He be Exalted, will place it wherever He wills on the Day of Resurrection, and Hell is in the seventh earth.
It was narrated from Ibn Mas`ud (may Allah be pleased with him) that Paradise is in the fourth heaven, and on the Day of Resurrection, Allah will place it wherever He wills. Hell is in the seventh earth, and on the Day of Resurrection, Allah will place it wherever He wills. Narrated by Ibn Mandah.
Mujahid said: I said to Ibn `Abbas: Where is Paradise? He said: Above seven heavens. I said: Where is Hell? He said: Beneath seven seas, which are one above another. Narrated by Ibn Mandah.
Ash-Shawkani said in Fat-h al-Qadir: What is best is to understand the statement on the basis of the view that is most widely accepted, for the requital of deeds is written in heaven and the divine will and decree descend from it, and Paradise and Hell are there. End quote.
To conclude: Paradise is above the seventh heaven, and its roof is the Throne. Hell is in the seventh earth, according to the correct view. And Allah is the Source of strength. End quote.
… as-Suyuti said in Itmam ad-Dirayah Sharh an-Niqayah: We cannot be certain about Hell, meaning that we say nothing concerning this issue, namely its location, because no one knows it except Allah. I know of no authentic hadith that could be relied upon concerning this matter.
And it was said that it [Hell] is beneath the earth, because of the report narrated by Ibn `Abd al-Barr, who classed it as weak (da`if), which was narrated from Ibn `Umar and attributed to the Prophet (blessings and peace of Allah be upon him): “No one should sail on the sea except one who is fighting [in Allah’s cause] or a pilgrim who is going to do Hajj or `umrah, for beneath the sea there is a fire …”
And it was said that it is on the face of the earth, because of the report narrated by Wahb, who said: Dhul-Qarnayn stood on the Mountain of Qaf and saw some smaller mountains… And he said: O Qaf, tell me about the greatness of Allah. It [the mountain] said: Our Lord is great indeed. Beyond me there is a land, the size of which is the distance of five hundred years’ travel by the distance of five hundred years travel, filled with mountains of snow which crowd one another. Were it not for that, I could have been burned because of Hell.
Al-Harith ibn Usamah narrated in his Musnad that `Abdullah ibn Salam said: Paradise is in the heavens and Hell is on earth. And it was said that the location of Hell is in the heavens. End quote from as-Suyuti.
Similarly, in At-Tadhkirah, al-Qurtubi said: This indicates that Hell is on the face of the earth, and Allah knows best where it is located on the earth. End quote.
Shaykh Ahmad Waliyullah ad-Dehlawi, the hadith scholar, said in his book Al-`Aqidah: There is no text which clearly states the locations [of Paradise and Hell]; rather they are wherever Allah, may He be Exalted, wills they should be, for we do not have comprehensive knowledge about Allah’s creation and the worlds that He has created. End quote.
I say: This is the most correct and most prudent view, in sha Allah.
Al-Mawsu`at al-`Aqadiyyah, 5/159.
See also: Yaqazah Uli al-I`tibar mimma warada fi Dhikr an-Nar wa As-hab an-Nar, by Siddiq Hasan Khan, pp. 23.
Conclusion:
There is no certainty about the present location of Hell, and this is the correct view, because there is no proven, definitive text that will put an end to the debate about it, as there are different reports from the early generations concerning this matter.
Secondly:
There is a place between Paradise and Hell which is called al-A`raf. It is a high barrier from which its occupants will look out at the people of Paradise and the people of Hell, then ultimately their Lord, may He be Glorified and Exalted, will admit them to His Paradise, and they will not enter Hell. The most correct of the scholarly views regarding them is that they are people whose good deeds and bad deeds are equal.
Allah, may He be Exalted, says:
{Between them there will be a barrier, and on its heights there will be men who will recognize each group by their marks. They will call out to the inhabitants of Paradise: Peace be upon you. They will not have entered it but they will hope [to do so].
And when their eyes are turned towards the inhabitants of hell, they will say: Our Lord, do not put us with people who are given to wrongdoing.
The people on the heights will call out to men whom they will recognize by their marks: Of what benefit to you were your great numbers and wealth and your scornful pride?
Are these the ones concerning whom you swore that Allah would never bestow His mercy upon them? [Now] enter Paradise; you will have no fear nor will you grieve} [Al-A`raf 7:46-49].
This barrier, which is called al-A`raf (the Heights) will be set up between Paradise and Hell in the hereafter; it does not exist at present. In the hereafter, the earth will be replaced with another earth, and so will the heavens, and Allah will place all of that wherever He wills. Thus there is no contradiction in that at all, and there is no confusion about it, praise be to Allah.
And Allah knows best.