diff --git a/edr_server/core/models/extents.py b/edr_server/core/models/extents.py
index 9d356a6..3e00f62 100644
--- a/edr_server/core/models/extents.py
+++ b/edr_server/core/models/extents.py
@@ -211,9 +211,25 @@ class VerticalExtent(EdrModel["VerticalExtent"]):
     #       * list of vertical levels (e.g. "2",10,"80","100"}
     #       The value `null` is supported and indicates an open vertical interval.
 
+    def __post_init__(self):
+        if not isinstance(self.values, List):
+            raise TypeError(
+                f'Expected List of values, received {type(self.values)}')
+        if not all(isinstance((invalid_value := value), (float, str)) for value in self.values):
+            raise TypeError(
+                f"Expected all float or string values, received value '{invalid_value}' of type {type(invalid_value)}")
+        if not isinstance(self.vrs, CrsObject):
+            raise TypeError(f'Expected CrsObject, received {type(self.vrs)}')
+
     @classmethod
     def _prepare_json_for_init(cls, json_dict: JsonDict) -> JsonDict:
         json_dict["vrs"] = CrsObject.from_wkt(json_dict["vrs"])
+
+        with suppress(KeyError):  # Remove things not required by __init__
+            # 'interval' stores the bounds, which is different from the 'intervals' argument to the __init__ method
+            del json_dict["interval"]
+            del json_dict["name"]
+
         return json_dict
 
     @classmethod
diff --git a/setup.cfg b/setup.cfg
index 0a2da31..25c1ce5 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -7,6 +7,7 @@ version = 0.1.0
 # We're affected by https://bugs.python.org/issue43923, so can only use 3.7 & 3.8
 python_requires = >=3.7,<3.9
 install_requires =
+    numpy
     shapely
     pyproj
     tornado>=6.1
diff --git a/tests/unit/core/models/test_extents.py b/tests/unit/core/models/test_extents.py
index 2d7e8b3..954fae4 100644
--- a/tests/unit/core/models/test_extents.py
+++ b/tests/unit/core/models/test_extents.py
@@ -1,9 +1,11 @@
 import unittest
 from datetime import datetime, timedelta
 from shapely.geometry import Polygon
+import numpy as np
 
-from edr_server.core.models.extents import TemporalExtent, SpatialExtent
+from edr_server.core.models.extents import TemporalExtent, SpatialExtent, VerticalExtent
 from edr_server.core.models.time import DateTimeInterval, Duration
+from edr_server.core.models.crs import CrsObject
 
 
 class TemporalExtentTest(unittest.TestCase):
@@ -443,3 +445,58 @@ def test_init_type_checking_crs(self):
 
         with self.assertRaisesRegex(TypeError, "Expected CrsObject, received <class 'str'>"):
             SpatialExtent(poly, input)
+
+
+class VerticalExtentTest(unittest.TestCase):
+
+    def test_from_json(self):
+        """
+        GIVEN a typical json_dict
+        WHEN from_json is called
+        THEN a VerticalExtent is returned
+        """
+        expected = VerticalExtent([1.65])
+
+        json_dict = {'interval': ['ScalarBounds(lower=1.65, upper=1.65)'],
+                     'values': [1.65],
+                     'vrs': 'VERTCRS["WGS_1984",VDATUM["World Geodetic System 1984"],CS[vertical,1],AXIS["ellipsoidal height (h)",up,LENGTHUNIT["metre",1,ID["EPSG",9001]]]]',
+                     'name': 'WGS_1984'}
+
+        actual = VerticalExtent.from_json(json_dict)
+
+        self.assertEqual(actual, expected)
+
+    def test_init_type_checking_values(self):
+        """
+        GIVEN a non-list
+        WHEN passed to VerticalExtent.values
+        THEN a TypeError is returned
+        """
+        heights = {"value": 4}
+
+        with self.assertRaisesRegex(TypeError, "Expected List of values, received <class 'dict'>"):
+            VerticalExtent(values=heights)
+
+    def test_init_type_checking_values_entry(self):
+        """
+        GIVEN a list of floats with one bad entry
+        WHEN passed to VerticalExtent.values
+        THEN a TypeError is returned with value and type
+        """
+        vals = list(np.arange(0, 1, 0.2))
+        vals.append([1])
+
+        with self.assertRaisesRegex(TypeError, r"Expected all float or string values, received value '\[1\]' of type <class 'list'>"):
+            VerticalExtent(values=vals)
+
+    def test_init_type_checking_vrs(self):
+        """
+        GIVEN a non-CrsObject input
+        WHEN passed to VerticalExtent
+        THEN a TypeError is returned
+        """
+        vals = list(np.arange(0, 1, 0.2))
+        input = "bad input"
+
+        with self.assertRaisesRegex(TypeError, "Expected CrsObject, received <class 'str'>"):
+            VerticalExtent(values=vals, vrs=input)