Although many students demonstrate considerable aptitude in manipulating equations and variables within academic environments, research consistently shows that they lack conceptual understanding; the deficit accounts for their difficulties in choosing appropriate equations or understanding the basic phenomena that undergird such equations. This study investigates undergraduate understanding of sight distance and stopping sight distance in introductory transportation courses. Although sight distance and stopping sight distance are fundamental concepts in transportation engineering, students demonstrate considerable difficulty in understanding these concepts and often rely on previous experience or preferred equations without relating them to specific phenomena of interest. Suggested approaches are offered for transportation engineering educators to improve their students' conceptual understanding.