diff --git a/dartwrf/prep_IC_prior.py b/dartwrf/prep_IC_prior.py
index a4d2a73d47c89cc2b983adb80dd16c0a9878cccd..c6775c6245553c05984f1aaec0a9732ce5cee32e 100755
--- a/dartwrf/prep_IC_prior.py
+++ b/dartwrf/prep_IC_prior.py
@@ -20,6 +20,11 @@ Ad 2: copies wrfrst to run_WRF directory
 def create_wrfrst_in_WRF_rundir(time, prior_init_time, prior_path_exp):
     """copies wrfrst to run_WRF directory (for next WRF run)
     """
+    # for documentation: Which prior was used? -> write into txt file
+    os.system('echo "'+prior_path_exp+'\n'+prior_init_time.strftime('/%Y-%m-%d_%H:%M/')
+                +'\n'+time.strftime('/wrfrst_d01_%Y-%m-%d_%H:%M:%S')+'" > '
+                +cluster.archivedir + time.strftime('/%Y-%m-%d_%H:%M/')+'link_to_prior.txt')
+
     for iens in range(1, exp.n_ens+1):
         clean_wrfdir(cluster.wrf_rundir(iens))