Breaking through

Those roots from the Populus trichocarpa are so strong they are growing through the pavement. The tree, called Alaskaösp in Icelandic, was planted very widely some 20-30 years ago. People didn't realise how fast the tree would grow, how big it would get, or how long it's roots would become. So about 10-15 years later, many people had problems with the tree, and many have been chopped down. When we moved into our house there were three of them on our neighbours lawn (right next to our lawn), and the casted a big shadow over our lawn, hindered our sight to the mountains and the roots were "everywhere". We were very happy to see them go.
But in the right place this can be a beautiful tree.