I'm going on an almost 6 months trip to the US and Canada.
As a Danish citizen I can use the Visa Waiver Program to stay for up to 90 days in the US.
I will start my journey in California and leave the US to go to Canada within the 90 days and will not come back since the a Canada side trip won't reset the 90 days allowance. I will fly from Canada to Europe without even transiting in the US.
To prove my intentions of not staying in the US more than the 90 days, will a bus ticket out of the country after say 80 days from Buffalo to Toronto (they are the cheapest) combined with showing my ticket leaving the North American continent suffice?
Do I actually need to exit the way that I intend at first - or could I go from Seattle to Vancouver if I somehow find myself going that way instead?
When exiting overland to Canada do I need to do something special at the border in order to be registered as having left the US inside the 90 days?