"The woman saith unto Him, Sir, I perceive that Thou art a prophet. Our fathers worshipped in this mountain; and Ye say, that in Jerusalem is the place where men ought to worship. Jesus saith unto her, Woman, believe Me, the hour cometh, when ye shall neither in this mountain, nor yet at Jerusalem, worship the Father... But the hour cometh, and now is, when the true worshippers shall worship the Father in spirit and in truth: for the Father seeketh such to worship Him" (John 4:19-21; 23).
Since born again believers in the Lord Jesus Christ direct our prayers to "our Father, which art in Heaven," there are no places of prayer upon the earth more sacred than any other (Matthew 6:9). Through Christ, we can pray any and everywhere, although it is true that we may have special and personal venues where we especially enjoy communion with God. This is fine so long as we don't view our prayers as more spiritual or devoted because they are prayed from supposedly "holy" sites. Doubtless many genuine supplications ascend to Heaven from jail cells, while many prayers ritualistically and insincerely offered in churches never penetrate the ceiling of the sanctuary.
As mentioned in a previous consideration, true prayer involves reality, and thus, heart. The heart of God calls to the heart of man, calling us to seek Him in humility, faith, deliberation, and most of all, in love. "Where?" is not the issue of prayer. "Why?" far more comprises the essence of genuine relationship between the Divine and the human. If our motivation involves the moving of the Holy Spirit in our hearts, along with our response thereunto, true prayer proceeds from Heaven to earth and back to Heaven. Our Lord has made plain in His Word that "place" is not the issue of prayer. We must be sure that we share His opinion, and pray accordingly.
"I will therefore that men pray everywhere, lifting up holy hands, without wrath and doubting."
(I Timothy 2:8)