Despite many decades of research, biofilm architecture and spreading mechanisms are still not clear because of the heterogenous 3D structure within biofilms. Here, patterned “slippery” lubricant‐infused porous surfaces are utilized to study biofilm structure of Pseudomonas aeruginosa , Stenotrophomonas maltophilia , and Staphylococcus aureus . It is found that bacteria are able to spread over bacteria‐repellent lubricant‐infused regions by using a mechanism, termed “biofilm bridges”. Here, it is demonstrated that bacteria use bridges to form interconnected networks between distant biofilm colonies. Detailed structure of bridges shows a spatial distribution of bacteria with an accumulation of respiratory active bacteria and biomass in the bridges. The core–shell structure of bridges formed by two‐species mixed population is illustrated. It is demonstrated that eDNA and nutrients have a strong effect on biofilm bridges formation. Thus, it is believed that biofilm bridging is important to reveal the structure and communication within biofilms.