今日馬祖列島的南、北竿二島，長久以來，乃時人所熟悉的「海防軍事要地」。明時稱作「竿塘山」的南、北竿島，自宋代起，便有「上、下干塘」、「上、下竿塘」、「南、北竿塘」、「官塘」、「關潼」和「關童」等各種不同之稱呼。因為，竿塘山位處福建省福州府閩江口外海中，係外敵進犯福州城要衝之地。因敵人進犯福建時，常由海上先襲取福州城再佔領全省；加上，福州城又有「偏殘淺露」之地形缺點。故，明帝國在一開始建構省城所在地「福州城」邊防時，便留意此缺失，即加強其防禦措致以補其不足，而攸關福州城海上邊防的竿塘山，自然亦是其構築海防的重點之一。為此，明帝國於洪武初年便設「垾寨」於上竿塘，二十年(1387)時為對抗倭患，便實施「墟地徙民」，除將「垾寨」撤走外，並將上、下竿塘山島民全數強遷回內地，而與此海禁政策配合推動的是「海防設施的擘建」。因為，明帝國十分重視福州城邊防措施的構築，除先前在福州城設置福州左、中、右三衛外，並於閩江河口兩側部署鎮東衛以及定海、梅花二個守禦千戶所，又在閩江口外北岸設立兵船基地――小埕水寨，該寨是以保衛福州城海上安危為首要目標，閩江口附近海域是其兵防佈署重點，透過戍寨衛、所官軍所組成的水師，抗拒侵賊於海中，而竿塘山便是其最重要的哨防地點。因為，小埕水寨兵船基地的建立，這支福州地區最強大的海上武力，加上先前在福州城附近陸岸上所構築的衛、所兵力，水、陸兵力的相互援引配合，使得自然條件頗受「大海」和「地形」制約的福州城，在安全上得到較堅固的保障。

Nowadays Nan-Gan Island and Bei-Gan Island are in Matsu archipelago called Gan-Tang-Shan by Ming Dynasty. Gan-Tang-Shan located on the sea out Min-Jiang estuary in Fu-Jian Province is the necessary passing position when enemies aggressed upon Fu-Jhou City. Therefore, in the beginning of Ming Dynasty, Ming government early dispatched an army to defend Gan-Tang-Shan. Later on, because Ming Dynasty must resist the Japanese pirates, it evacuated the army of Gan-Tang-Shan and migrated the inhabitants of the island to the land. Afterward, Ming government set up a good deal of troops near Fu-Jhou City at the same time set up a naval base and disposed a lot of battleships in the outside of Min-Jiang estuary. Hence Gan-Tang-Shan became the most important defense strongpoint. Ming Dynasty reached the aim of protecting Fu-Jhou City by means of above-mentioned armed activities.