The colonial grid planned by the British in colonial North America took hold in a severe iteration in the late 18th century in the area of what is now Toronto, Canada. The British sought to maintain greater geographic control after their loss of the Thirteen Colonies to the south, resulting in a tightly planned and imposed grid by British land surveyors, a grid that ignored the natural beauty and topography of the area. Toronto’s general topography drops in elevation from north to south but historically it was incised at intervals by undulating ravines of the nine rivers flowing southward into Lake Ontario. The colonial grid imposed by the British was the initial step toward the disappearance of many of those ravines, first by building the bridges that spanned them to define the grid, then by filling them with industrial refuse and culverting the rivers that flowed through them. Later still in the 20th century, the significant ravine in this picture was almost levelled by displaced soil from urban expansion and subway construction, sometimes entirely erasing the natural undulating topography in favor of the grid. Garrison Creek, the stream running through this part of the city, is still flowing below grade in a series of large sewers below the green spaces in the photo.