This paper presents the design and field tests of an intelligent robotic system for archaeological exploration. The system is designed for recording the internal environment of the underground ancient tombs. The recorded data is used for the preservation of antiques inside the ancient tombs as well as for providing the valuable references to the archaeological research. The whole system is modular and minimized in size that can be adapted for two different archaeological situations during the exploration of the ancient tombs. The robotic system can enter the covered ancient tombs through the digging holes prepared by the regular archaeological exploration. One size of the vertical digging hole is less than 12 centimeter in diameter, and the other is 50 centimeter in diameter. The archaeologists can operate on the remote station to control the robotic system with wired communication. The field test results are finally presented for validation of this archaeological robotic system design.