The high speed data pathway system is used to convey data signals to integrated circuits connected to mother and daughter boards. The integrated circuits include a package and an integrated circuit chip carried by the package. An internal transmission line is carried by the package and coupled to the integrated circuit chip. The package includes both input and output connections for the internal transmission line. A high speed pathway is formed by serially connecting the internal transmission lines with external transmission lines to form a unified transmission medium. Advantageously, the internal transmission lines, external transmission lines and the connection between them have substantially corresponding characteristic impedances.