The Zaporizhian Sich complex on Khortytsia is a reconstruction rather than an original fortress, but it is still a useful way into Cossack history. Wooden walls, a church, workshops, and open courtyards show the rough outline of the military camp society that grew along the lower Dnipro.
Treat it as interpretation, not archaeology. Its value is that it makes a complicated idea visible: a frontier community, armed and self-governing, whose memory still runs through Ukrainian culture.