New York State's location in the Northeast makes it a natural launching pad. From the city you can reach New Jersey, Connecticut, and the Hudson Valley in under an hour; from the Buffalo area, both Niagara Falls and Toronto are within easy striking distance.
New Jersey
Cross the George Washington Bridge and you're in Fort Lee in minutes. From there, PATH trains reach Newark in 22 minutes — worth it for the Newark Museum, which has a serious collection of American art and a remarkable trove of Tibetan artifacts, plus a preserved Victorian mansion on-site.
New England
If you're in the northeastern part of the state, Vermont, Massachusetts, and New Hampshire are all within a few hours by car. Amtrak's Vermonter runs from Penn Station to St. Albans, Vermont, if you'd rather not drive. New England's historic towns and fall foliage make it one of the better day-trip regions in the country.
Canada
From the Buffalo area, the Canadian side of Niagara Falls is 30 minutes away — and it genuinely is the better view. Toronto is an hour and a half further, big enough to fill a full day with the ROM, Kensington Market, and the waterfront. You'll need a passport to cross the border, no exceptions.