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In October I will be going from Europe (Germany) to Canada and then continuing to Buffalo before flying to Miami. I will leave my rental car at the Canadian side of Niagara Falls and cross the rainbow bridge in the evening by foot.
I will not have a visa because ESTA only applies for boat/airplane travels. Will they care if I just get there with my luggage and without a car and apply directly for a visa or is it a normal procedure? Can I prepare something (visa application etc.)?