C. F. Keil and Franz Delitzsch on Joshua 19:46

Jos 19:46 Me-jarkon, i.e., aquae flavedinis, and Rakkon, are unknown; but from the clause which follows, “with the territory before Japho,” it must have been in the neighbourhood of Joppa (Jaffa). “The territory before Japho” includes the places in the environs of Joppa. Consequently Joppa itself does not appear to have belonged to the territory of Dan, although, according to Jdg 5:17, the Danites must have had possession of this town. Japho, the well-known port of Palestine (2Ch 2:15; Ezr 3:7; Jon 1:3), which the Greeks called Ἰόππη (Joppa), the present Jaffa (see v. Raumer, Pal. pp. 204-5, and Ritter, Erdk. xvi. pp. 574ff.).