Caudal epidural anesthesia remains the most frequently performed regional anesthesia technique in pediatric age group for subumbilical surgeries, used to provide both intraoperative and post operative pain relief .Here, needle is placed through sacral hiatus to deliver medications into the epidural space. It was first introduced as landmark based blind technique. This block is deceptively easy to perform but rare and potentially serious complications can occur with a blind approach into the epidural space such as inadvertent intravenous injection, dural puncture and post dural puncture headache, intrathecal injection and total spinal anaesthesia, repeated attempts, failure to block, rectal puncture, etc.The evolution of US technology has provided a tool that can circumvent some of the inherent limitations of conventional epidural anaesthesia and analgesia. Successful caudal blockade depends upon correct placement of the needle in the caudal space.  Using ultrasound guidance, needles can be inserted into the caudal epidural space under real time imaging or using a planned trajectory subsequent to a review of the relevant anatomy on prepuncture scan . This study aims at determining the optimal angle of needle insertion for a successful caudal block and to avoid puncture of the bone and other complications . This study aims at determining the anatomy of the caudal space .