re: Visiting the U.S from down under

With your 8/10hr drive limit, you could pretty much go anywhere in New England. New England (especially Boston and Philadelphia (not really part of New England)) will have plenty of historical landmarks since both are integral to the founding of the country.

- Portland, Maine and the Maine coast up to Bar Harbor (Acadia National Park) are nice. Portland has good breweries and a good restaurants for a smaller size city.

- Cape Cod is couple hours drive (you can also ferry to Provincetown from Boston), Martha's Vinyard and Nantucket are a ferry rides from the southern shores of Cape Cod.

- Vermont, New Hampshire and Western Massachusetts have a lot of very scenic areas too, if that is an interest.

- Newport, Rhodes Island - Couple hours south of Boston is filled to Mansions of the rich and famous when it was summer play ground of New York Cities elite in 1800 & early 1900's.

- If you drive to Niagara you'll pass close or through the Finger Lakes, Catskills and Adirondacks, depending on your route.