Canada is bounded, in part, by the waters of the Pacific Ocean, the Atlantic Ocean and the Arctic Ocean. There are no "seas" that are actually in Canada, although Canada claims territorial rights in the above oceans.
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We have the Beaufort, Prince Gustav Adolf, Lincoln and Labrador Seas and if the Caspian is a Sea then so could some of the Great Lakes be called seas. Sailing some of them in a storm will have anyone understand why they are more like seas than lakes.
Black and Caspian seas
The Ligurian Sea and the Adriatic Sea are two seas that border Italy. The other two sea that border Italy are the Mediterranean Sea and the Ionian Sea.
The North Sea and the Mediterranean Sea.
Black Sea and Caspian Sea
Sea of Okhotsk and Bering Sea.
You'll find there are more than two....... Are you including the Red sea and the Mediteranian? Incidentally, a "cape" is the point on land where two seas meet.
The Mediterranean and Red Seas. Additionally, the border between Egypt and Israel and Egypt and Gaza is a border fence, so that's visible, but it's not geographic.
The Mediterranean Sea [into which it flows] and the Red Sea
Lake Michigan is the eastern border and Lake Superior is part of the northern border.
North Sea and Baltic Sea
Countries that bored the Ukraine are Russia, Belarus, Poland, Slovakia, Hungary, Romania and Moldova. Seas that border the Ukraine are the Black Sea and the Sea of Azov.
The Trans-antarctic Mountain Range stretches across part of the Antarctic continent. Two seas on the sides of the continent are the Weddell Sea and the Ross Sea. There are no seas on Antarctica itself.