The purpose of this thesis is to explore and analyze the guan (观) watchtowers in the Shanglinyuan imperial garden of the western Han dynasty (202-8 BCE) via the lens of landscape architecture and archaeology. By sorting through literature and archaeological evidence, this thesis attempts to reconstruct the form and characteristics of the guan watchtower, as well as to discuss its meaning and significance in the imperial garden. It argues that the watchtowers in the Shanglinyuan were important design components in the imperial garden which underline the quest for the abodes of the immortals and the power of designed visibility. By integrating multiple sources of evidence and interdisciplinary literatures and theories, this thesis offers a new perspective in understanding and investigating the design of early Chinese gardens.