Abstract
According to the Samkuk Saki(History of Three Nations), An-ap pond was constructed in the 14th year of the reign of King Mun-$\mu$ But this period precedes the unification of Shilla(in the 16th year the reign of king Mun-mu) and Shilla was at war. Therefore I suppose the 16th year of the King's reign is just the time of the commencement of the construction of the pond. But the real construction had not been started before the 16th year of the King's reign, after the unification of the three nations into Shilla Dynasty. Another record of making a larger pond(the 19th year of the reign of king Kyung-duk) may signify the enlargement of the very pond that had been built the 16th year of King Mun-mu's reign. Korean traditional belief was the belief in the Dragon, the Mountain God, and the Heavenly God and these was deeply rooted in the Royal family and perhaps had influenced the building of An-ap pond. Namely it is explained that Em-hae Jun sympolizes the An-ap pond itself as the sea and the Dragon lived in the sea and also the mountain built in the East bank of An-ap pond is related to the Mountain God. And also Taoism's Sin Sun Sa-Sang(Paradise philosophy) had influenced the building of the three legendary immortal islands, called Yong Ju, Bang-Jang, Bong-Rae in the An-ap pond. It is supposed that the age of An-ap pond from the above mentioned facts and inferences and we can also understand the influence of the Royal family customs on the building of An-ap pond. The inscriptions on the vessels and architectural accessories suggest us the influence of the Royal family customs on the construction of An-ap pond.