Markaad ka fikirto dharka goonnada yaryar, miyaad u malaynaysaa naqshadaha yaryar ee 1960-yadii? Ha werwerin, goonnada yaryar ee PVC neon wali waa wax la soo dhaafay. Maalmahan naqshadeeyayaasha ayaa soo bandhigaya mowjad cusub oo cusub oo nashqado goono yaryar ah oo casri ah. Dharka gaaban ee casriga ah – ha ahaato xiddigaha dhagaxyada, amiiradaha, ama haweenka xirfadlayaasha ah – hadda waxay tusi karaan lugahaaga quruxda badan siyaabo kala duwan oo gaar ah oo casri ah.