Grist: Meandering south from Cold Lake on small roads, I entered a new landscape. The boreal forest of northern Alberta gave way to rolling prairie, grain silos, and rural crossroads. The oil sands were now behind me - or rather, flowing beneath me. Every road had pipeline crossing signs or ditches for new lines alongside or piles of pipe sections waiting to be laid. All pipes led to the place I was headed: Hardisty, home to Canadas largest oil depot and the site where the Keystone XL was slated to begin....