diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 88c7228..546c461 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -57,7 +57,7 @@ build_debian:
     Section: web
     Priority: optional
     Architecture: all
-    Depends: python3 (>= 3.7), python3-jinja2, python3-bottle, python3-dateutil, python3-icalendar, python3-isodate, python3-tz
+    Depends: python3 (>= 3.7), python3-jinja2, python3-bottle, python3-dateutil, python3-icalendar, python3-isodate
     Description: Scrape iCalendar endpoints and present their data in a
      timeseries format.  A small service that scrapes iCalendar files
      served over HTTP, parses their contents and returns a timeseries
diff --git a/icalendar_timeseries_server/config.py b/icalendar_timeseries_server/config.py
index c3d18df..b763527 100644
--- a/icalendar_timeseries_server/config.py
+++ b/icalendar_timeseries_server/config.py
@@ -8,9 +8,10 @@ import urllib.request
 import sys
 import logging
 
-import pytz
 import jinja2
 from isodate import Duration, parse_duration
+from dateutil import tz
+from datetime import tzinfo
 
 from icalendar_timeseries_server import __version__
 
@@ -93,7 +94,7 @@ class Config:
             config = dict()
         self._addr: str = _keycheck('addr', config, str, '', default_value='127.0.0.1')
         self._port: int = _keycheck('port', config, int, '', default_value=8090)
-        self._tz: pytz.tzinfo = _parse_timezone('tz', config, '', default_value='UTC')
+        self._tz: tzinfo = _parse_timezone('tz', config, '', default_value='UTC')
         self._start_delta: Duration = _parse_timedelta('start_delta', config, '', default_value='PT')
         self._end_delta: Duration = _parse_timedelta('end_delta', config, '', default_value='P30D')
         self._calendars: Dict[str, CalendarConfig] = self._parse_calendars_config('calendars', config, '')
@@ -120,7 +121,7 @@ class Config:
         return self._port
 
     @property
-    def tz(self) -> pytz.tzinfo:
+    def tz(self) -> tzinfo:
         return self._tz
 
     @property
@@ -185,7 +186,10 @@ def _parse_timezone(key: str,
                     path: str,
                     default_value: Any = None) -> Any:
     zonename: str = _keycheck(key, config, str, path, default_value=default_value)
-    return pytz.timezone(zonename)
+    zone: zoneinfo = tz.gettz(zonename)
+    if zone is None:
+        raise ValueError(f'Unknown timezone: {zonename}')
+    return zone
 
 
 def _parse_key_replace(key: str,
diff --git a/icalendar_timeseries_server/test/test_config.py b/icalendar_timeseries_server/test/test_config.py
index c0f7601..3d9be55 100644
--- a/icalendar_timeseries_server/test/test_config.py
+++ b/icalendar_timeseries_server/test/test_config.py
@@ -2,9 +2,9 @@
 import unittest
 
 import json
-import pytz
-from datetime import timedelta
+from datetime import timedelta, tzinfo
 
+from dateutil import tz
 from isodate.duration import Duration
 
 from icalendar_timeseries_server.config import _keycheck, _parse_timedelta, _parse_timezone, Config
@@ -113,10 +113,10 @@ class ConfigTest(unittest.TestCase):
             'tz': 'Europe/Zurich',
             'notz': 'North/Winterfell'
         }
-        self.assertEqual(_parse_timezone('tz', config, ''), pytz.timezone('Europe/Zurich'))
+        self.assertEqual(_parse_timezone('tz', config, ''), tz.gettz('Europe/Zurich'))
         self.assertEqual(_parse_timezone('def', config, '', default_value='Europe/Berlin'),
-                         pytz.timezone('Europe/Berlin'))
-        with self.assertRaises(pytz.exceptions.UnknownTimeZoneError):
+                         tz.gettz('Europe/Berlin'))
+        with self.assertRaises(ValueError):
             _parse_timezone('notz', config, '')
 
     def test_parse_full_config_valid(self):
@@ -125,7 +125,7 @@ class ConfigTest(unittest.TestCase):
         self.assertEqual(config.port, 8090)
         self.assertEqual(config.start_delta, Duration(hours=-3))
         self.assertEqual(config.end_delta, Duration(days=30))
-        self.assertEqual(config.tz, pytz.timezone('Europe/Zurich'))
+        self.assertEqual(config.tz, tz.gettz('Europe/Zurich'))
 
     def test_parse_calendars(self):
         config = Config(json.loads(_CONFIG_VALID))
diff --git a/setup.py b/setup.py
index e5aaae3..dfb999b 100755
--- a/setup.py
+++ b/setup.py
@@ -18,11 +18,10 @@ setup(
     python_requires='>=3.6',
     install_requires=[
         'bottle',
-        'python-dateutil',
+        'python-dateutil>=2.8',
         'icalendar',
         'isodate',
-        'jinja2',
-        'pytz'
+        'jinja2'
     ],
     entry_points={
         'console_scripts': [