

The visual appeal of these installations can enhance the charm of historic sites, parks, and plazas. For instance, in a historic district, ornamental bollards adorned with intricate finials can pay homage to the architectural style of the area, while maintaining necessary safety measures. Parks may opt for more natural-looking materials that blend harmoniously with their surroundings, thereby enhancing the outdoor experience without detracting from nature.
Civil engineers in Rome invented the concept of underground sewer to rid their cities of plagues caused by human contact with waste. Their water sources that they used for consumption were also contaminated as they served as open sewers. The underground sewers made sure that that waste stayed out of reach of humans and was deposited by these sewers further downstream. For periodic cleaning, they also provided access ways that were covered with stone lids that we call manholes today. Incidentally, these stone access way covers are still seen in Jerash, Jordan which was a Roman city in the old days.