After World War I up to the ‘70s, low-clinker binder solutions were adopted in several countries for specialized applications, valued for their low heat release, energy efficiency, and enhanced resistance to various forms of chemical attack. However, much of the knowledge surrounding these binders and the infrastructures built with them has been lost over time. As sustainability becomes a pressing priority, the use of low-clinker binders is gaining attention. Yet, modern low-clinker concrete systems often face significant challenges, particularly with their susceptibility to carbonation and concerns about reinforcement corrosion. To address these durability issues, this study investigates historical infrastructures built with similar low-clinker binders, offering valuable insights into their long-term performance. By analyzing the composition and durability of these older structures—both in situ and through modern accelerated testing methods—this research aims to enhance the durability predictions of today’s low-clinker solutions and improve their potential service life in future applications.