That bottom photo shows an undergroud pipeline after construction. It was taken from an article about how pipelines like that make for great hiking trails. The land has to be maintained so no tree roots comprimise the pipe, so it is a win-win. Some are above ground, some are buried.

edit: https://archive.is/jvu1H#selection-691.0-691.166

That bottom photo shows an undergroud pipeline after construction. It was taken from an article about how pipelines like that make for great hiking trails. The land has to be maintained so no tree roots comprimise the pipe, so it is a win-win.

Some are above ground, some are buried.