The occurrence of tree lines started to increase from the Renaissance period. At that time, however, it was merely landscaping in precisely designed ornamental gardens. Planting lines of trees along public roads started to be more frequent in the early 18th century, coming from the French school of modern road building. Trees became a fully-fledged part of a technical installation - a road. At first, their function was primarily aesthetic - helping to incorporate the road structure into the countryside. Later on, other economical and practical advantages were discovered.