Albert Barnes Commentary 1 Samuel 21:1

"Then came David to Nob to Ahimelech the priest: and Ahimelech came to meet David trembling, and said unto him, Why art thou alone, and no man with thee?" — 1 Samuel 21:1 (ASV)

Nob was a city of the priests; the high priest resided there, and the tabernacle was pitched there (1 Samuel 21:4, 6, 9; 22:10). It was situated on the road from the north to Jerusalem, near Anathoth, and within sight of the holy city (Isaiah 10:32; Nehemiah 11:32). But its site has not been identified with certainty.