The exponential increase in mobile traffic demand is driving numerous research efforts towards the development of next-generation 6G communications, which are expected to support peak data-rates up to 1 Tbps, thereby requiring the development of novel ultra-high-capacity wireless communications technologies. Within this context, the OptWire project will exploit the usage of free-space optics (FSO) for terabit-capable wireless communications. FSO provides a series of key advantages, including the availability of unregulated spectrum, its immunity to electromagnetic interference and compatibility with lower-cost transceivers inherited from fiber-based communications. However, FSO still suffers from the highly detrimental impact of atmospheric turbulence, which causes beam wandering. In order to face this challenge, the OptWire project will bring together specialized research groups on optical communication engineering, computational fluid dynamics modelling and machine learning. The main aim of the project is to comprehensively model and mitigate the impact of turbulent phenomena on ultra-high-speed FSO communications. Behavioral model extraction will be based on extensive experimental campaigns within controlled laboratory conditions (wind-tunnel and custom-design atmospheric chamber scenarios), followed by big data analysis using deep-learning algorithms. After extensive validation and refinement, the model can be used for quasi-real-time prediction of FSO power budget depending on instantaneous turbulence measurements. This information will be critical for the optimized design of mitigation measures, which include the use of adaptive modulation and coding, beam steering and multiple-input-multiple-output transmission diversity. Finally, benefiting from the state-of-the-art ORCIP research infrastructure, the OptWire project includes a field-deployment stage, providing the ultimate test towards realistic and challenging outdoor turbulence conditions.