Formerly filled with alpine lakes, these valleys are now sheeted with flat alluvial soil and occupied by human settlements, and are drained by rivers which flow along them before they make their way to the north through narrow gorges pierced in the mountain-walls.
Covering the higher parts of the south-western Palaeozoic area in most places are rolling hills of boulder clay or stony moraines; while the lower levels are plains gently sloping toward the nearest of the Great Lakes and sheeted with silt deposited in more ancient lakes when the St Lawrence outlet was blocked with ice at the end of the glacial period.
These can be open containers, sheeted or can have a lockable lid.
The sheeted surfaces of the rest of the model are treated with sanding sealer then tissue covered.
Spots on the mountains of Scotland, Northern Ireland, North Wales, and the Lake District of England are sheeted over with its firm flat tufts, often several feet across.
