Canada is the second largest landmass in the world. The Canadian soil is extended from the Atlantic Ocean in east to the Pacific Ocean in west. The northern border of Canada reaches the Arctic Ocean. We can therefore consider Canada a land which is surrounded by three seas or rather oceans on three different sides. Of course part of the western border of Canada is common with Alaska a US state.
The southern border of Canada is different. Part of the southern border reaches the soil of the United States. The rest of the southern border crosses one of the four Great Lakes, the Superior Lake, Lake Huron, Lake Erie, and Lake Ontario from west to east consecutively. All of these lakes are fresh water lakes. The Superior Lake is the largest fresh water lake in the world. The following map shows what I just explained.