If Gallup were to take a poll on places in nature people think are 'spiritual' I am sure that mountains would rank high on the results. They are awe-inspiring in their shear immensity, they even point upward, to heaven, reason tells us. This reasoning is exactly what we find in the Promised Land, before the Israelites settle there. "You must demolish completely all the places where the nations whom you are about to dispossess served their gods, on the mountain heights, on the hills, and under every spreading tree," we read in ch.12 v.2--the message is that while man thinks that spiritual connectedness happens on a mountain God says worship happens where people gather in his name, "God [will choose the place] and put his name there" (ch.12 v.5).
The positions are dichotomous, man uses his reason to find a place(s) to be spiritually in tune while God creates a location where his name will be the focus (again v.5) rather than a place. While seeking out God in this way our journey has resonations with the psalmist, "I lift my eyes up to the hills--where does my help come from? / My help comes from the Lord, maker of heaven and earth (Psalm 121). What the Psalmist knew was that the pagan worship that happened on the hills and mountains was marbles and bubble gum to the Lord who made those hills.
God's call is for his people to "seek the place that the Lord your God will choose out of all your tribes as his habitation to put his name there. You shall go there, bringing your [sacrifices]" (v.5-6). The idea is that this one place, where God's name will be stamped, will signify--more than a place to get good spiritual-antenna reception--but a space that offers Israel an opportunity to be unified, together, face to face, and under the name YHWH. Also, I like that God calls Israel to "seek the place"; this maintains his sovereignty as the judge while leading Israel, and us, into participation with him who was, is, and is to come.
Finally, the end of chapter 12 describes the depravity which some pagan worship practices had sunk to. We read, "do not inquire: 'How did these nations worship their gods? I also want to do the same.' You must not do the same for the Lord your God, because every abhorrent thing that the Lord hates they have done for their gods. They would even burn their sons and their daughters in the fire to their gods" (v.31). This chilling passage bares witness to what happens when "reason" is let loose to do the business of faith. The human faculty of reason is good, surely it is God gave it to us, but the spiritual gift of faith must renew it before it attends to the spiritual things. Yet, these drastic spiritual perversions we see in Deuteronomy twelve will continue since man cannot escape the void in him that screams for God, thus "reason" will scramble, attempting anything to get a 'right' spiritual connection--as Deuteronomy ch.12 tells us: spiritualizing creation (v.2) and destroying it (v. 31) are signs of the fatal turn.