Premise: The fascinating exhibits include a section of the massive chain that the Byzantines used to stretch across the mouth of the Golden Horn to keep out enemy ships, as well as captured enemy cannon and military banners, the campaign tents from which the Ottoman sultans controlled their armies, and examples of uniforms, armour, and weapons from the earliest days of the Empire down to the 20th century.

Hypothesis: A chain was used and stretched to prevent enemy ships from entering.
Relation: entailment