A voice of one crying out in the desert:
"Prepare the way of the Lord, make straight his paths.
Every valley shall be filled and every mountain and hill shall be made low.
The winding roads shall be made straight, and the rough ways made smooth,
and all flesh shall see the salvation of God."
I don't know if there was still a memory of Alexander the Great's funeral procession at the time of John the Baptist's preaching. Alexander died in Persia and his body was placed in a huge funerary temple and dragged through the Holy Land ]down to Alexandria to be entombed. It would have been much simpler to have put the body on a ship but instead it went by land, but the land journey of the corpse with a huge retinue meant that Alexander's glory was seen.
The transfer of his body was a huge engineering feat, it meant a road way had to built, literally mountains or at least hills had to be laid low and valley raised up, twisted tracks had to be made straight. A Way suitable for camels, or even a vast army was not suitable for Alexander's juggernaut, a paved way would have to be constructed and built by local labour.
Alexander's funeral was the most spectacular of the ancient world but it would seem was not an exception. It would seem paved roads were very much associated with Kings, Empires, Armies and Gods. Those ancient Roman roads were not for moving herds or crops or merchandise around but for armies and Imperial messengers, to even use the road invariably involved applying for permission or a licence and was restricted to particular "chosen" people.
Johns call therefore for making a "Way for the Lord" is for a Divine Way, a road that involves effort to build and maintain, it is sacred processional route not a winding goat track.
Today's reading from Isaiah says the following:
A highway will be there, called the holy way; No one unclean may pass over it, nor fools go astray on it. No lion will be there, nor beast of prey go up to be met upon it. It is for those with a journey to make, and on it the redeemed will walk. Those whom the LORD has ransomed will return and enter Zion singing, crowned with everlasting joy; They will meet with joy and gladness, sorrow and mourning will flee.
Even to have access to it one has to be in a state of Grace, "No one unclean may pass over it". Nor is it a place for the dissident, "nor fools go astray on it".