Let the bible answer your question. First you have to get the context of the conversation Jesus was having, then you need to look at how multiple translators have treated the statement he made. Jesus was asked by the people who opposed him when the Kingdom would come. He was the representative of that Kingdom, they should have realized it was right in front of them! However their hardheartedness prevented them from seeing this. Jesus then makes the statement in question. It is at this point we need to examine what translators have done with this verse:
New International Version (©1984)
nor will people say, 'Here it is,' or 'There it is,' because the kingdom of God is within you."
New Living Translation (©2007)
You won't be able to say, 'Here it is!' or 'It's over there!' For the Kingdom of God is already among you."
English Standard Version (©2001)
nor will they say, ‘Look, here it is!’ or ‘There!’ for behold, the kingdom of God is in the midst of you.”
Note please the variance of words used: 'within' 'in the midst of' and 'among'. The first translation quoted actually has a footnote which says 'or among'. When I see all these things I cannot help but realize Jesus was referring to himself being there with them, not that the Kingdom was 'within' the people who questioned him, especially since they were his enemies!