diff --git a/frontend/src/api/index.js b/frontend/src/api/index.js
index 78ea2d5..b5827ab 100644
--- a/frontend/src/api/index.js
+++ b/frontend/src/api/index.js
@@ -202,6 +202,11 @@ export const locationsApi = {
   },
   delete(id) {
     return api.delete(`/locations/${id}`)
+  },
+  types: {
+    list() {
+      return api.get('/locations/types')
+    }
   }
 }
 
diff --git a/frontend/src/views/settings/LocationsList.vue b/frontend/src/views/settings/LocationsList.vue
index 1d57c5e..0f55f45 100644
--- a/frontend/src/views/settings/LocationsList.vue
+++ b/frontend/src/views/settings/LocationsList.vue
@@ -25,6 +25,7 @@
             <thead>
               <tr>
                 <th>Location Name</th>
+                <th>Type</th>
                 <th>Building</th>
                 <th>Floor</th>
                 <th>Room</th>
@@ -35,6 +36,7 @@
             <tbody>
               <tr v-for="loc in locations" :key="loc.locationid">
                 <td>{{ loc.locationname }}</td>
+                <td>{{ loc.locationtypename || '-' }}</td>
                 <td>{{ loc.building || '-' }}</td>
                 <td>{{ loc.floor || '-' }}</td>
                 <td>{{ loc.room || '-' }}</td>
@@ -55,7 +57,7 @@
                 </td>
               </tr>
               <tr v-if="locations.length === 0">
-                <td colspan="6" style="text-align: center; color: var(--text-light);">
+                <td colspan="7" style="text-align: center; color: var(--text-light);">
                   No locations found
                 </td>
               </tr>
@@ -125,6 +127,32 @@
               </div>
             </div>
 
+            <div class="form-row">
+              <div class="form-group">
+                <label for="locationtypeid">Type</label>
+                <select id="locationtypeid" v-model="form.locationtypeid" class="form-control">
+                  <option value="">Select type...</option>
+                  <option v-for="t in locationTypes" :key="t.locationtypeid" :value="t.locationtypeid">
+                    {{ t.locationtype }}
+                  </option>
+                </select>
+              </div>
+
+              <div class="form-group">
+                <label for="parentlocationid">Parent Location</label>
+                <select id="parentlocationid" v-model="form.parentlocationid" class="form-control">
+                  <option value="">None</option>
+                  <option
+                    v-for="l in parentOptions"
+                    :key="l.locationid"
+                    :value="l.locationid"
+                  >
+                    {{ l.locationname }}
+                  </option>
+                </select>
+              </div>
+            </div>
+
             <div class="form-group">
               <label for="description">Description</label>
               <textarea
@@ -180,11 +208,13 @@
 </template>
 
 <script setup>
-import { ref, onMounted } from 'vue'
+import { ref, computed, onMounted } from 'vue'
 import { locationsApi } from '../../api'
 import PaginationBar from '../../components/PaginationBar.vue'
 
 const locations = ref([])
+const locationTypes = ref([])
+const allLocations = ref([])
 const loading = ref(true)
 const search = ref('')
 const page = ref(1)
@@ -205,12 +235,29 @@ const form = ref({
   floor: '',
   room: '',
   description: '',
+  locationtypeid: '',
+  parentlocationid: '',
   mapimage: ''
 })
 
+// parent options = all locations except the one being edited (no self-parent)
+const parentOptions = computed(() =>
+  allLocations.value.filter(l => l.locationid !== editingLocation.value?.locationid)
+)
+
 let searchTimeout = null
 
-onMounted(() => {
+onMounted(async () => {
+  try {
+    const [typesRes, allRes] = await Promise.all([
+      locationsApi.types.list(),
+      locationsApi.list({ perpage: 100 })
+    ])
+    locationTypes.value = typesRes.data.data || []
+    allLocations.value = allRes.data.data || []
+  } catch (err) {
+    console.error('Error loading location types:', err)
+  }
   loadLocations()
 })
 
@@ -261,6 +308,8 @@ function openModal(loc = null) {
       floor: loc.floor || '',
       room: loc.room || '',
       description: loc.description || '',
+      locationtypeid: loc.locationtypeid || '',
+      parentlocationid: loc.parentlocationid || '',
       mapimage: loc.mapimage || ''
     }
   } else {
@@ -270,6 +319,8 @@ function openModal(loc = null) {
       floor: '',
       room: '',
       description: '',
+      locationtypeid: '',
+      parentlocationid: '',
       mapimage: ''
     }
   }
@@ -287,10 +338,15 @@ async function saveLocation() {
   saving.value = true
 
   try {
+    const payload = {
+      ...form.value,
+      locationtypeid: form.value.locationtypeid || null,
+      parentlocationid: form.value.parentlocationid || null
+    }
     if (editingLocation.value) {
-      await locationsApi.update(editingLocation.value.locationid, form.value)
+      await locationsApi.update(editingLocation.value.locationid, payload)
     } else {
-      await locationsApi.create(form.value)
+      await locationsApi.create(payload)
     }
     closeModal()
     loadLocations()
diff --git a/migrations/versions/7c03_locationtypes.py b/migrations/versions/7c03_locationtypes.py
new file mode 100644
index 0000000..4b2de0f
--- /dev/null
+++ b/migrations/versions/7c03_locationtypes.py
@@ -0,0 +1,56 @@
+"""Add locationtypes + locations tree (ADR-001)
+
+Creates the locationtypes lookup and extends locations with locationtypeid +
+parentlocationid (self-FK), so sites can classify locations and build a
+location tree (sections, cells, sub-cells, operations, etc.). Seeds the
+canonical location types.
+
+Revision ID: 7c03_locationtypes
+Revises: 7c02_app_isrequired
+Create Date: 2026-06-26
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+revision = '7c03_locationtypes'
+down_revision = '7c02_app_isrequired'
+branch_labels = None
+depends_on = None
+
+_TYPES = ['section', 'cell', 'subcell', 'operation', 'meetingroom', 'lab',
+          'office', 'storage', 'hallway', 'networkcloset', 'building']
+
+
+def upgrade():
+    op.create_table(
+        'locationtypes',
+        sa.Column('locationtypeid', sa.Integer(), primary_key=True),
+        sa.Column('locationtype', sa.String(length=50), nullable=False, unique=True),
+        sa.Column('description', sa.Text(), nullable=True),
+        sa.Column('createddate', sa.DateTime(), nullable=True),
+        sa.Column('modifieddate', sa.DateTime(), nullable=True),
+        sa.Column('isactive', sa.Boolean(), nullable=True),
+    )
+    with op.batch_alter_table('locations') as batch_op:
+        batch_op.add_column(sa.Column('locationtypeid', sa.Integer(), nullable=True))
+        batch_op.add_column(sa.Column('parentlocationid', sa.Integer(), nullable=True))
+        batch_op.create_foreign_key('fk_locations_locationtype', 'locationtypes',
+                                    ['locationtypeid'], ['locationtypeid'])
+        batch_op.create_foreign_key('fk_locations_parent', 'locations',
+                                    ['parentlocationid'], ['locationid'])
+
+    lt = sa.table('locationtypes',
+                  sa.column('locationtype', sa.String),
+                  sa.column('isactive', sa.Boolean))
+    op.bulk_insert(lt, [{'locationtype': t, 'isactive': True} for t in _TYPES])
+
+
+def downgrade():
+    with op.batch_alter_table('locations') as batch_op:
+        batch_op.drop_constraint('fk_locations_parent', type_='foreignkey')
+        batch_op.drop_constraint('fk_locations_locationtype', type_='foreignkey')
+        batch_op.drop_column('parentlocationid')
+        batch_op.drop_column('locationtypeid')
+    op.drop_table('locationtypes')
diff --git a/shopdb/cli/__init__.py b/shopdb/cli/__init__.py
index a2202ea..381b2c0 100644
--- a/shopdb/cli/__init__.py
+++ b/shopdb/cli/__init__.py
@@ -42,7 +42,7 @@ def seed_cli():
 def seed_reference_data():
     """Seed reference data (machine types, statuses, etc.)."""
     from shopdb.extensions import db
-    from shopdb.core.models import MachineType, OperatingSystem, AssetStatus
+    from shopdb.core.models import MachineType, OperatingSystem, AssetStatus, LocationType
     from shopdb.core.models.relationship import RelationshipType
 
     # Machine types
@@ -85,6 +85,14 @@ def seed_reference_data():
         elif existing.isactive is not True:
             existing.isactive = True
 
+    # Location types (ADR-001)
+    location_types = ['section', 'cell', 'subcell', 'operation', 'meetingroom',
+                      'lab', 'office', 'storage', 'hallway', 'networkcloset',
+                      'building']
+    for lt in location_types:
+        if not LocationType.query.filter_by(locationtype=lt).first():
+            db.session.add(LocationType(locationtype=lt, isactive=True))
+
     # Operating systems
     os_list = [
         {'osname': 'Windows 10', 'osversion': '10.0'},
diff --git a/shopdb/core/api/locations.py b/shopdb/core/api/locations.py
index cb88386..8e963ec 100644
--- a/shopdb/core/api/locations.py
+++ b/shopdb/core/api/locations.py
@@ -4,7 +4,7 @@ from flask import Blueprint, request
 from flask_jwt_extended import jwt_required
 
 from shopdb.extensions import db
-from shopdb.core.models import Location
+from shopdb.core.models import Location, LocationType
 from shopdb.utils.responses import (
     success_response,
     error_response,
@@ -16,6 +16,19 @@ from shopdb.utils.pagination import get_pagination_params, paginate_query
 locations_bp = Blueprint('locations', __name__)
 
 
+@locations_bp.route('/types', methods=['GET'])
+@jwt_required(optional=True)
+def list_location_types():
+    """List all location types."""
+    types = LocationType.query.filter_by(isactive=True).order_by(
+        LocationType.locationtype).all()
+    return success_response([{
+        'locationtypeid': t.locationtypeid,
+        'locationtype': t.locationtype,
+        'description': t.description,
+    } for t in types])
+
+
 @locations_bp.route('', methods=['GET'])
 @jwt_required(optional=True)
 def list_locations():
@@ -81,6 +94,8 @@ def create_location():
         floor=data.get('floor'),
         room=data.get('room'),
         description=data.get('description'),
+        locationtypeid=data.get('locationtypeid'),
+        parentlocationid=data.get('parentlocationid'),
         mapimage=data.get('mapimage'),
         mapwidth=data.get('mapwidth'),
         mapheight=data.get('mapheight')
@@ -117,7 +132,9 @@ def update_location(location_id: int):
                 http_code=409
             )
 
-    for key in ['locationname', 'building', 'floor', 'room', 'description', 'mapimage', 'mapwidth', 'mapheight', 'isactive']:
+    for key in ['locationname', 'building', 'floor', 'room', 'description',
+                'locationtypeid', 'parentlocationid', 'mapimage', 'mapwidth',
+                'mapheight', 'isactive']:
         if key in data:
             setattr(loc, key, data[key])
 
diff --git a/shopdb/core/models/__init__.py b/shopdb/core/models/__init__.py
index 312660f..4ffd337 100644
--- a/shopdb/core/models/__init__.py
+++ b/shopdb/core/models/__init__.py
@@ -6,7 +6,7 @@ from .machine import MachineType
 from .vendor import Vendor
 from .model import Model
 from .businessunit import BusinessUnit
-from .location import Location
+from .location import Location, LocationType
 from .operatingsystem import OperatingSystem
 from .relationship import AssetRelationship, RelationshipType
 from .communication import Communication, CommunicationType
@@ -32,6 +32,7 @@ __all__ = [
     'Model',
     'BusinessUnit',
     'Location',
+    'LocationType',
     'OperatingSystem',
     # Relationships
     'AssetRelationship',
diff --git a/shopdb/core/models/location.py b/shopdb/core/models/location.py
index 7d96bf9..480ce92 100644
--- a/shopdb/core/models/location.py
+++ b/shopdb/core/models/location.py
@@ -1,9 +1,25 @@
-"""Location model."""
+"""Location + LocationType models."""
 
 from shopdb.extensions import db
 from .base import BaseModel
 
 
+class LocationType(BaseModel):
+    """Location classification (ADR-001 shared reference data).
+
+    Seeded values: section, cell, subcell, operation, meetingroom, lab,
+    office, storage, hallway, networkcloset, building. Sites can extend.
+    """
+    __tablename__ = 'locationtypes'
+
+    locationtypeid = db.Column(db.Integer, primary_key=True)
+    locationtype = db.Column(db.String(50), unique=True, nullable=False)
+    description = db.Column(db.Text)
+
+    def __repr__(self):
+        return f"<LocationType {self.locationtype}>"
+
+
 class Location(BaseModel):
     """Physical location model."""
     __tablename__ = 'locations'
@@ -15,6 +31,19 @@ class Location(BaseModel):
     room = db.Column(db.String(50))
     description = db.Column(db.Text)
 
+    # Classification + tree (ADR-001)
+    locationtypeid = db.Column(
+        db.Integer,
+        db.ForeignKey('locationtypes.locationtypeid'),
+        nullable=True
+    )
+    parentlocationid = db.Column(
+        db.Integer,
+        db.ForeignKey('locations.locationid'),
+        nullable=True,
+        comment='Parent location for the site location tree'
+    )
+
     # Map configuration
     mapimage = db.Column(db.String(500), comment='Path to floor map image')
     mapwidth = db.Column(db.Integer)
@@ -26,5 +55,15 @@ class Location(BaseModel):
     mapx = db.Column(db.Integer, comment='Default X coordinate for assets at this location')
     mapy = db.Column(db.Integer, comment='Default Y coordinate for assets at this location')
 
+    # Relationships
+    locationtype = db.relationship('LocationType')
+    parent = db.relationship('Location', remote_side=[locationid])
+
+    def to_dict(self):
+        data = super().to_dict()
+        data['locationtypename'] = self.locationtype.locationtype if self.locationtype else None
+        data['parentlocationname'] = self.parent.locationname if self.parent else None
+        return data
+
     def __repr__(self):
         return f"<Location {self.locationname}>"