What is another word for formidable defenses?
Pronunciation: [fɔːmˈɪdəbə͡l dɪfˈɛnsɪz] (IPA) 
When talking about formidable defenses, there are a number of synonymous terms that come to mind. These may include impregnable fortifications, impenetrable barriers, unassailable ramparts, or invincible walls. Other terms that might be used include impenetrable defenses, unconquerable fortifications, or insurmountable barriers. All of these terms convey the sense that a particular defense is extremely difficult to overcome or breach. This might be due to physical barriers like walls or moats, high-tech surveillance and alarm systems, or simply the strength and skill of the defenders. Whatever the reason, the use of such terms is typically intended to communicate a sense of strength, security, and impregnability.
