What did the Samaritan woman leave behind when she hurried back into town?

Answer: Her water jar

She left her water jar and told the town, "Come, see a man who told me everything I ever did."

“Then the woman left her water jar, went back into the town, and said to the people, “Come, see a man who told me everything I ever did. Could this be the Christ?””— John 4:28-29 (BSB)