For Sufficiently Large Definitions Of Near

Firebase 23 on Hill 562 "near" the villages of Plei Hodrong Thoung and Plei Ya Bo; 23 miles Southwest of Pleiku air field, 10 miles north of the SF Camp at Plei Me.

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Plei Me is the southern point of the triangle.  Plei Ya Bo is the western point, Plei Hodrong Thoung is the eastern.  Pleiku is off the map to the northeast.

Firebase 23 is at the little kink of the east-west leg of the triangle.  There is no 562m elevation there.

 It's more like Hill 450.

This is the only likely hill between the "nearby" villages and fitting the distances from the other two landmarks.

Assuming the QL19 highway is the same as Route 6C this is a good spot.  It's within the 7 mile, 105mm howitzer range of the road (about 5 miles), but too far from Plei Me (13.6 miles) to support it.

I think, now, that the "nearby" villages mark points on route 6C which is a smuggling path from over the Cambodian border rather than an actual road.  In that case, the path goes right past the firebase.

That's also why the commies want it destroyed, bringing us to the beginning of the campaign!