sentences:  The highway is not included as a part of the National Highway System, a system of highways deemed most important for the country's economy, mobility and defense.When it was designated in 1935, SR 378 existed just in the form of its current northern segment between SR 217 and SR 141.Two years later, SR 378 would take on its current look when it was extended via a short concurrency with SR 217 heading east, then onto its current southern stretch to a junction with SR 243.