diff --git a/csv-to-ics.py b/csv-to-ics.py
index 9ac8a35..700e9e0 100644
--- a/csv-to-ics.py
+++ b/csv-to-ics.py
@@ -1,15 +1,34 @@
 import csv
 import os
+import uuid
+import json
 from ics import Calendar, Event
 from datetime import datetime
 import pytz
 
+UID_STORE_FILE = "event_uids.json"
+
+def load_uids():
+    """Load the UID mappings from a JSON file."""
+    if os.path.exists(UID_STORE_FILE):
+        with open(UID_STORE_FILE, "r") as file:
+            return json.load(file)
+    return {}
+
+def save_uids(uids):
+    """Save the UID mappings to a JSON file."""
+    with open(UID_STORE_FILE, "w") as file:
+        json.dump(uids, file)
+
 def generate_ical_from_csv(csv_file):
+    # Load existing UIDs
+    uids = load_uids()
+
     # Generate the output .ics file name
     ical_file = os.path.splitext(csv_file)[0] + '.ics'
 
     # Define CET time zone
-    cet = pytz.timezone('Europe/Berlin')  # CET is commonly represented by Berlin
+    cet = pytz.timezone('Europe/Berlin')
 
     # Create a new calendar
     calendar = Calendar()
@@ -27,29 +46,31 @@ def generate_ical_from_csv(csv_file):
                     start_time = row['start time'].strip()  # Expected format: HH:MM
                     end_time = row['end time'].strip()  # Expected format: HH:MM
                     location = row['Location']
-
                     # Combine date and time using the updated date format and apply CET
                     start_datetime = cet.localize(datetime.strptime(f"{date} {start_time}", "%d.%m.%Y %H:%M"))
                     end_datetime = cet.localize(datetime.strptime(f"{date} {end_time}", "%d.%m.%Y %H:%M"))
-                    uid = f"{date}{start_time}@lak2024.leben-in-gross-doelln.de"
+                    # Create a unique key for the event
+                    event_key = f"{description}_{date}_{start_time}_{location}"
+                    # Retrieve or generate a UID
+                    uid = uids.get(event_key, str(uuid.uuid4()))
+                    uids[event_key] = uid
                     # Create a new event
                     event = Event()
-                    event.created = cet.localize(datetime.now())
-                    event.uid = uid
-                    event.name = f"{description} (Gastgeber: {host})"  # Include the host in the event name
+                    event.name = f"{description} (Gastgeber: {host})"
                     event.begin = start_datetime
                     event.end = end_datetime
                     event.location = location
-
+                    event.uid = uid  # Set the unique identifier
+                    event.last_modified = datetime.now()  # Timestamp for updates
                     # Add the event to the calendar
                     calendar.events.add(event)
-
                 except Exception as e:
                     print(f"Error processing row: {row}. Error: {e}")
-
         # Write the calendar to an iCal file
         with open(ical_file, mode='w', encoding='utf-8') as file:
             file.writelines(calendar)
+        # Save UIDs for future use
+        save_uids(uids)
 
         print(f"iCal file created: {ical_file}")