dated 1931 shows an area of marsh. Since then its use as a landfill site has turned it into 30 metre high hill. It has now been capped off with soil but such sites continue to generate methane for years afterwards. This manhole is one of the methane vents.
I think these rock filled ditches and embankments are are to catch storm water and prevent big flows which might carry soil away.
php file date: 2023 Jun 23 19:26:00
$_COOKIE['vpt_dims']=×, $_COOKIE['pathome']=, $_COOKIE['em2px']=14 - more
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