Between the blocks

 is a stash featured in S.T.A.L.K.E.R.: Lost Alpha.

"Put my rucksack in-between some concrete blocks for later."

- PDA description

Overview

 * Located near the junction of Rostok and the Wild Territory (as far as SoC places them).
 * Area is fairly radioactive.
 * Blind dogs and Pseudodogs have been encountered in the immediate vicinity.