Detroit
The closest border of Canada from Columbus, Ohio is the border with the province of Ontario. Specifically, the closest crossing point would be the Detroit-Windsor border crossing, which is approximately 200 miles north of Columbus. This border crossing is a major international crossing point between the United States and Canada, connecting Detroit, Michigan, and Windsor, Ontario.
Niagara Falls
There is not CLOSE border crossing between Texas and Canada, but you probably go through Detroit.
Assuming you mean "Toronto", Ontario, and assuming you mean a border crossing into the USA, try Fort Erie/Buffalo.
260km or 3 hours drive or 161 miles to the closest border crossing is at Carway directly south of Calgary.
The nearest U.S. border crossing at Prescott, Ontario/Ogdensburg NY. Or at Cornwall - Massena or St. Regis, NY.
That is easy to answer! There are absolutely no oceans in Pennsylvania. In fact, no oceans exist "in" or inside any State of the United States. The closest ocean to Pennsylvania is the Atlantic Ocean, but it does not touch Pennsylvania.
The closest U.S. border to Ottawa, Canada, is the border with New York State. Specifically, the nearest border crossing is the Thousand Islands Bridge, located about 50 miles south of Ottawa, which connects Ontario with New York. This crossing is part of the larger area known as the St. Lawrence Seaway, facilitating travel between the two countries.
The closest border crossing into Mexico from Las Vegas is at the San Ysidro Port of Entry, located in San Diego, California. This crossing is approximately 330 miles southwest of Las Vegas. Travelers can reach it by taking Interstate 15 south, which connects directly to San Diego. The San Ysidro crossing is one of the busiest land crossings in the world.
The closest US border town to Guadalajara is Laredo in Texas. It is located approximately 320 miles north of Guadalajara and is a common crossing point for travelers between Mexico and the United States.
Mount Baker is approximately 30 miles (48 kilometers) south of the Canadian border. The closest border crossing is at the Sumas-Huntingdon crossing, which provides access to Canada. The distance may vary slightly depending on the specific route taken.
Prescott-Ogdensburg Border Crossing