In a geographical area as large and complex as North America, there will inevitably be multiple presentations. Over time, some of these will be removed from the website as new ones come into take their place. On this connecting page for North America presentations (as one can see from the links on the left hand side of this page), the existing page for Alaska has been supplemented by three new pages containing presentations for Canada and the USA.
Below are some 'sampler' photos (some of which appear in the slide presentations) which epitomise each geographical area/country in the links.
I hope you enjoy the presentations!