 The road also provides access to the University of Texas at Austin's McDonald Observatory.In 1927, the Texas Legislature authorized the Texas Highway Department, a precursor agency to TxDOT, to construct Davis Mountains State Park Highway after what was then the State Parks Board had failed to acquire parkland for a state park within the Davis Mountains.The road was to include portions of the present SH 118 and State Highway 166 now known as the Davis Mountains Scenic Loop.