Smith's Bible Dictionary

Baca (weeping), The Valley of, A valley in Palestine, through which the exiled Psalmist sees in vision the pilgrims passing in their march towards the sanctuary of Jehovah at Zion. (Psalm 84:6) That it was a real locality is most probable from the use of the definite article before the name. The rendering of the Targum is Gehenna, i.e. the Ge-Hinnom or ravine below Mount Zion. This locality agrees well with the mention of became (Authorized Version "mulberry") trees in (2 Samuel 5:23)