diff --git a/src/c3nav/mapdata/api.py b/src/c3nav/mapdata/api.py
index 51ab22b0..3a8fe401 100644
--- a/src/c3nav/mapdata/api.py
+++ b/src/c3nav/mapdata/api.py
@@ -17,6 +17,7 @@ from rest_framework.viewsets import GenericViewSet, ReadOnlyModelViewSet, ViewSe
 
 from c3nav.mapdata.models import AccessRestriction, Building, Door, Hole, LocationGroup, MapUpdate, Source, Space
 from c3nav.mapdata.models.access import AccessPermission
+from c3nav.mapdata.models.geometry.base import GeometryMixin
 from c3nav.mapdata.models.geometry.level import LevelGeometryMixin
 from c3nav.mapdata.models.geometry.space import POI, Area, Column, LineObstacle, Obstacle, SpaceGeometryMixin, Stair
 from c3nav.mapdata.models.level import Level
@@ -300,10 +301,14 @@ class LocationViewSet(RetrieveModelMixin, GenericViewSet):
                 for obj in queryset:
                     # noinspection PyStatementEffect
                     obj.subtitle, obj.order
+                    if isinstance(obj, GeometryMixin):
+                        # noinspection PyStatementEffect
+                        obj.centroid
 
                 cache.set(queryset_cache_key, queryset, 300)
 
-            result = tuple(obj.serialize(include_type=True, detailed=detailed, geometry=geometry) for obj in queryset)
+            result = tuple(obj.serialize(include_type=True, detailed=detailed, geometry=geometry, simple_geometry=True)
+                           for obj in queryset)
             cache.set(cache_key, result, 300)
 
         return Response(result)
diff --git a/src/c3nav/mapdata/models/geometry/base.py b/src/c3nav/mapdata/models/geometry/base.py
index 0b182d9b..5ff700c5 100644
--- a/src/c3nav/mapdata/models/geometry/base.py
+++ b/src/c3nav/mapdata/models/geometry/base.py
@@ -1,6 +1,8 @@
+import math
 from collections import OrderedDict
 
 from django.db import models
+from django.utils.functional import cached_property
 from django.utils.translation import ugettext_lazy as _
 from shapely.geometry import Point, mapping
 
@@ -59,16 +61,25 @@ class GeometryMixin(SerializableMixin):
             result['geomtype'] = cls._meta.get_field('geometry').geomtype
         return result
 
+    @cached_property
+    def centroid(self):
+        return self.geometry.centroid
+
     def serialize(self, geometry=True, **kwargs):
         result = super().serialize(geometry=geometry, **kwargs)
         if geometry:
             result.move_to_end('geometry')
         return result
 
-    def _serialize(self, geometry=True, **kwargs):
-        result = super()._serialize(**kwargs)
+    def _serialize(self, geometry=True, simple_geometry=False, **kwargs):
+        result = super()._serialize(simple_geometry=simple_geometry, **kwargs)
         if geometry:
             result['geometry'] = format_geojson(mapping(self.geometry), round=False)
+        if simple_geometry:
+            result['point'] = (self.level_id, ) + tuple(round(i, 2) for i in self.centroid.coords[0])
+            if not isinstance(self.geometry, Point):
+                result['bounds'] = ((int(math.floor(self.miny)), int(math.floor(self.minx))),
+                                    (int(math.ceil(self.maxy)), int(math.ceil(self.maxx))))
         return result
 
     def get_shadow_geojson(self):
diff --git a/src/c3nav/mapdata/models/geometry/space.py b/src/c3nav/mapdata/models/geometry/space.py
index 30855049..d96dfa8f 100644
--- a/src/c3nav/mapdata/models/geometry/space.py
+++ b/src/c3nav/mapdata/models/geometry/space.py
@@ -1,4 +1,5 @@
 from django.db import models
+from django.utils.functional import cached_property
 from django.utils.text import format_lazy
 from django.utils.translation import ugettext_lazy as _
 from shapely.geometry import CAP_STYLE, JOIN_STYLE, mapping
@@ -16,11 +17,9 @@ class SpaceGeometryMixin(GeometryMixin):
     class Meta:
         abstract = True
 
-    def _serialize(self, space=True, **kwargs):
-        result = super()._serialize(**kwargs)
-        if space:
-            result['space'] = self.space_id
-        return result
+    @cached_property
+    def level_id(self):
+        return self.space.level_id
 
     def get_geojson_properties(self, *args, **kwargs) -> dict:
         result = super().get_geojson_properties(*args, **kwargs)
diff --git a/src/c3nav/mapdata/models/locations.py b/src/c3nav/mapdata/models/locations.py
index 548b677c..2bd67a80 100644
--- a/src/c3nav/mapdata/models/locations.py
+++ b/src/c3nav/mapdata/models/locations.py
@@ -83,7 +83,8 @@ class Location(LocationSlug, AccessRestrictionMixin, TitledMixin, models.Model):
         result = super().serialize(detailed=detailed, **kwargs)
         if not detailed:
             result = OrderedDict((
-                (name, result[name]) for name in ('slug', 'title', 'subtitle')
+                (name, result[name]) for name in ('id', 'slug', 'title', 'subtitle', 'point', 'bounds', 'locations')
+                if name in result
             ))
         return result
 
@@ -246,10 +247,12 @@ class LocationGroup(Location, models.Model):
         self.orig_category_id = self.category_id
         self.orig_color = self.color
 
-    def _serialize(self, **kwargs):
-        result = super()._serialize(**kwargs)
+    def _serialize(self, simple_geometry=False, **kwargs):
+        result = super()._serialize(simple_geometry=simple_geometry, **kwargs)
         result['category'] = self.category_id
         result['color'] = self.color
+        if simple_geometry:
+            result['locations'] = tuple(obj.pk for obj in getattr(self, 'locations', ()))
         return result
 
     @property
diff --git a/src/c3nav/mapdata/utils/json.py b/src/c3nav/mapdata/utils/json.py
index ebcc810c..302390de 100644
--- a/src/c3nav/mapdata/utils/json.py
+++ b/src/c3nav/mapdata/utils/json.py
@@ -6,7 +6,7 @@ def _preencode(data, magic_marker, in_coords=False, in_groups=False):
     if isinstance(data, dict):
         data = data.copy()
         for name, value in tuple(data.items()):
-            if name == 'bounds' and isinstance(value, (tuple, list)):
+            if name in ('bounds', 'point', 'locations') and isinstance(value, (tuple, list)):
                 data[name] = magic_marker+json.dumps(value)+magic_marker
             else:
                 data[name] = _preencode(value, magic_marker,