diff --git a/python/run_validator.py b/python/run_validator.py
new file mode 100644
index 00000000..1bbfbaf8
--- /dev/null
+++ b/python/run_validator.py
@@ -0,0 +1,138 @@
+import os, argparse
+from ngen.config.realization import NgenRealization
+from ngen.config.hydrofabric import CatchmentGeoJSON , NexusGeoJSON 
+from ngen.config.validate import validate_paths
+import re
+import geopandas
+
+def validate(catchments,realization_file=None):
+
+    relative_dir     = os.path.dirname(os.path.dirname(realization_file))
+
+    print(f'Done\nValidating {realization_file}')
+    serialized_realization = NgenRealization.parse_file(realization_file)
+    serialized_realization.resolve_paths(relative_to=relative_dir)
+    val = validate_paths(serialized_realization)
+    if len(val) > 0:
+        raise Exception(f'{val[0].value} does not exist!')
+            
+    print(f'Done\nValidating individual catchment forcing paths')
+    foring_dir    = os.path.join(relative_dir,serialized_realization.global_config.forcing.path)
+    forcing_files = sorted([x for _,_,x in os.walk(foring_dir)][0])
+    ncatchments = len(catchments)
+    catchments = sorted(catchments)
+    write_int = 1000    
+    for j, jcatch in enumerate(catchments):        
+        if j + 1 % write_int == 0: 
+            print(f'{j/ncatchments}%')
+        jid         = re.findall(r'\d+', jcatch)[0]
+        pattern     = serialized_realization.global_config.forcing.file_pattern
+        jcatch_pattern = pattern.replace('{{id}}',jid)
+        compiled       = re.compile(jcatch_pattern)      
+
+        jfile = forcing_files[j]     
+        assert bool(compiled.match(jfile)), f"{jcatch} -> Forcing file {jfile} does not match pattern specified {pattern}"          
+
+    print(f'\nNGen run folder is valid\n')
+
+def validate_data_dir(data_dir):
+
+    forcing_files    = []
+    catchment_file   = None
+    nexus_file       = None
+    realization_file = None
+    geopackage_file  = None
+    for path, _, files in os.walk(data_dir):
+        for jfile in files:
+            jfile_path = os.path.join(path,jfile)
+            if jfile_path.find('config') >= 0:
+                if jfile_path.find('catchments') >= 0:
+                    if catchment_file is None:                         
+                        catchment_file = jfile_path
+                    else: 
+                        raise Exception('This run directory contains more than a single catchment file, remove all but one.')
+                if jfile_path.find('nexus') >= 0: 
+                    if nexus_file is None: 
+                        nexus_file = jfile_path
+                    else: 
+                        raise Exception('This run directory contains more than a single nexus file, remove all but one.')
+                if jfile_path.find('realization') >= 0: 
+                    if realization_file is None: 
+                        realization_file = jfile_path
+                    else: 
+                        raise Exception('This run directory contains more than a single realization file, remove all but one.')
+                if jfile_path.find('.gpkg') >= 0: 
+                    if geopackage_file is None: 
+                        geopackage_file = jfile_path
+                    else: 
+                        raise Exception('This run directory contains more than a single geopackage file, remove all but one.')                    
+            if jfile_path.find('forcing') >= 0 and jfile_path.find('forcing_metadata') < 0: 
+                forcing_files.append(jfile_path) 
+
+    if not geopackage_file:
+        file_list = [catchment_file,nexus_file,realization_file]
+    else:
+        file_list = [geopackage_file,realization_file]
+        if catchment_file or nexus_file: raise Exception('The spatial domain must only be defined with either a geopackage, or catchment/nexus files. Not both.')
+    if any([x is None for x in file_list]):
+        raise Exception(f'Missing configuration file!')      
+
+    print(f'Configurations found! Retrieving catchment data...')
+
+    if geopackage_file:
+        catchments     = geopandas.read_file(geopackage_file, layer='divides')
+        catchment_list = list(catchments['divide_id'])
+        # Nexus validation?
+    else:
+        print(f'Validating {catchment_file}')
+        serialized_catchments = CatchmentGeoJSON.parse_file(catchment_file)
+        catchment_list = []
+        for jfeat in serialized_catchments.features:
+            id   = jfeat.id
+            if id is None: id = jfeat.properties.id # discrepancy between geopandas and pydantic
+            catchment_list.append(id)
+
+        print(f'Done\nValidating {nexus_file}')
+        NexusGeoJSON.parse_file(nexus_file)         
+    
+    validate(catchment_list,realization_file)
+
+if __name__ == "__main__":
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--data_dir",
+        dest="data_dir", 
+        type=str,
+        help="Path to the ngen input data folder", 
+        required=False
+    )
+    parser.add_argument(
+        "--tarball",
+        dest="tarball", 
+        type=str, 
+        help="Path to tarball to be validated as ngen input data folder", 
+        required=False
+    )
+    args = parser.parse_args()
+
+    if args.data_dir:
+        data_dir = args.data_dir
+        ii_delete_folder = False
+    elif args.tarball:
+        data_dir = '/tmp/ngen_data_dir'
+        if os.path.exists(data_dir): 
+            os.system(f'rm -rf {data_dir}')
+        os.mkdir(data_dir)
+        os.system(f'tar -xzf {args.tarball} -C {data_dir}')
+        ii_delete_folder = True
+    elif args.data_dir and args.tarball:
+        raise Exception('Must specify either data folder path or tarball path, not both.')
+    else:
+        raise Exception('No options set!')
+    
+    assert os.path.exists(data_dir), f"{data_dir} is an invalid directory"
+
+    validate_data_dir(data_dir)
+
+    if ii_delete_folder: os.system('rm -rf /tmp/ngen_data_dir')