I have spent many hours researching that particular question, but do not have a definitive answer for you. I will give you some of the Scriptures which may or may not clear this up for you.
I am not sure but I have come to these possible conclusions:
Hell and the bottomless pit may indeed be the same place.
Eze 31:2, 3,16, and 17 KJV
2 Son of man, speak unto Pharaoh king of Egypt, and to his multitude; Whom art thou like in thy greatness?
3 Behold, the Assyrian was a cedar in Lebanon with fair branches, and with a shadowing shroud, and of an high stature; and his top was among the thick boughs.
16 I made the nations to shake at the sound of his fall, when I cast him down to hell with them that descend into the pit: and all the trees of Eden, the choice and best of Lebanon, all that drink water, shall be comforted in the nether parts of the earth.
17 They also went down into hell with him unto them that be slain with the sword; and they that were his arm, that dwelt under his shadow in the midst of the heathen.
I am intrigued by the part that says:
I made the nations to shake at the sound of his fall, when I cast him down to hell with them that descend into the pit:
There is also a Proverb which causes me to believe that they may be the same, but different from the grave.
Proverbs 1:12 KJV
Let us swallow them up alive as the grave; and whole, as those that go down into the pit:
and the following Psalm seems to indicate that Hell is separate from the grave.
Psalms 30:3 KJV
O Lord, thou hast brought up my soul from the grave: thou hast kept me alive, that I should not go down to
the pit.
As far as the lake of fire Jesus said that it was prepared as a place of eternal punishment for the Devil and the fallen angels
Mat 25:41 KJV
Then shall he say also unto them on the left hand, Depart from me, ye cursed, into everlasting fire, prepared
for the devil and his angels:
Revelation tells us that it will also be the place for eternal punishment for the unsaved.
Revelation 14:9 through 11 KJV
9 And the third angel followed them, saying with a loud voice, If any man worship the beast and his
image, and receive his mark in his forehead, or in his hand,
10 The same shall drink of the wine of the wrath of God, which is poured out without mixture into the cup of his indignation; and he shall be tormented with fire and brimstone in the presence of the holy angels, and in the presence of the Lamb:
11 And the smoke of their torment ascendeth up for ever and ever: and they have no rest day nor night, who worship the beast and his image, and whosoever receiveth the mark of his name.
and I have concluded most possibly Hell and the bottomless pit may indeed be one and the same; and is a temporary holding place for at least some of the fallen angels, as well as those who reject salvation, to await the great white throne judgment.
I have also concluded that the grave is a temporary holding place for Christians to await the judgment of the righteous, but I still have not been able to reconcile that with Jesus telling the thief on the cross that today he would be with Jesus in Paradise. I do have a possible solution for that , but will keep that to myself since I have not researched it completely.