Sundial introduction: The sundial, also known as the "sundial", is a timing instrument in ancient my country that uses the shadow of the sun to distinguish time. It is a major invention of mankind in the field of astronomical timing and has been used for thousands of years. The stone sundial in the Cultural Expo Park is made up of five large circular disks stacked in decreasing order, with the sundial at the top. The base of the sundial is decorated with exquisite patterns and the waves of time. The dial surface is made of granite, with a diameter of 170 cm and a thickness of 18 cm. There are 12 uneven large grids on the front and back sides, each large grid representing two hours. The pointer is called the "dial needle" and is made of copper. It is 80 centimeters long and passes vertically through the center of the disk. It plays the role of a standard pole. Therefore, the sundial needle is also called "watch". The moving shadow of the sundial needle seems to be the hands of a modern clock, and the dial surface is the surface of the clock to show the time.