The economic, political and social well-being of European citizens relies on secure information and communication technologies (ICT). Our current ICT security relies in a large part on algorithmic methods that are threatened by constant progress in computing hardware and software, among which quantum computing must be seriously considered. Its potential realization has triggered the development of alternatives to currently-used public key encryption, in particular quantum key distribution (QKD), where security is built within the physical layer and based on the laws of quantum physics. The promise that QKD holds for the future of ICT-dependent societies has been recognized world-wide, including in China and the USA, but the creation of widely-available QKD-based ICT infrastructure and its broad adoption remain an open challenge. A key asset to bridge this gap between QKD technology providers and end users is the establishment and operation of an experimental facility that serves, and helps developing, the quantum communication ecosystem. This is where the OPENQKD projects comes into play. Its main aim is to raise awareness of the maturity of QKD and its seamless integration into existing security solutions and networks for a wide range of use-cases. This is done by working directly with end-users to test and validate end-to-end security for various businesses and industry sectors based on QKD. In particular, the OPENQKD project set up many testbed sites across Europe (approx. 20 different locations) to bring the technology to as many potential customers as possible. The testbeds replicated real world use cases as closely as possible with deployed optical fiber infrastructure and locations at the end-user premises to house the QKD and other network equipment. In order to demonstrate seamless integration into the security chain, both QKD and classical encryption devices were adapted, according to standardized specifications, to allow a direct hand over of keys. Since the use-case demonstration are core to the project, demonstrations covered a wide range of sectors such as, critical infrastructure protection, data center interconnect, securing of medical data, banking, securing governmental communication and many others.