Kovalier bastion

Sight of Kovalier bastion from curtain near to Kruglaya (Round) tower. There was so called Trubnaya (Horn) tower on that place in the old times. It was reconstructed to bastion in 17 AD. So the progress in offensive weapons (arbalest - cannon - missile) degrades significance of defensive fortifications (tower - bastion - bunker) as art of war and way of life.