diff --git a/pgcommitfest/commitfest/feeds.py b/pgcommitfest/commitfest/feeds.py
index 8a1250df..83c47bfc 100644
--- a/pgcommitfest/commitfest/feeds.py
+++ b/pgcommitfest/commitfest/feeds.py
@@ -1,5 +1,17 @@
+from __future__ import annotations
+
 from django.contrib.syndication.views import Feed
 
+from datetime import timedelta
+from typing import TYPE_CHECKING
+
+from icalendar import Calendar, Event
+
+if TYPE_CHECKING:
+    from collections.abc import Iterable
+
+    from .models import CommitFest
+
 
 class ActivityFeed(Feed):
     title = description = "Commitfest Activity Log"
@@ -34,3 +46,31 @@ def item_link(self, item):
 
     def item_pubdate(self, item):
         return item["date"]
+
+
+def calendar(commitfests: Iterable[CommitFest]) -> Calendar:
+    """
+    Build an RFC 5545 iCalendar document with one all-day VEVENT per
+    commitfest, covering its start and end date.
+    """
+    calendar = Calendar.new(
+        prodid="-//PostgreSQL Commitfest//commitfest.postgresql.org//EN",
+        name="PostgreSQL Commitfests",
+        description="Start and end dates of PostgreSQL Commitfests",
+        method="PUBLISH",
+    )
+
+    for cf in commitfests:
+        event = Event.new(
+            uid=f"commitfest-{cf.name}@commitfest.postgresql.org",
+            summary=cf.title,
+            start=cf.startdate,
+            # DTEND is exclusive for all-day events, so add a day to make the
+            # last day of the commitfest show up as included on the calendar.
+            end=cf.enddate + timedelta(days=1),
+            description=f"Status: {cf.statusstring}",
+            url=f"https://commitfest.postgresql.org/{cf.id}/",
+        )
+        calendar.add_component(event)
+
+    return calendar
diff --git a/pgcommitfest/commitfest/templates/archive.html b/pgcommitfest/commitfest/templates/archive.html
index 6d983df1..7f9087f2 100644
--- a/pgcommitfest/commitfest/templates/archive.html
+++ b/pgcommitfest/commitfest/templates/archive.html
@@ -1,5 +1,6 @@
 {%extends "base.html"%}
 {%block contents%}
+ <p><a href="/commitfests.ics">Subscribe to Commitfest dates (ICS)</a></p>
  <ul>
   {%for c in commitfests%}
    <li><a href="/{{c.id}}/">{{c}}</a> ({{c.statusstring}} - {{c.periodstring}})</li>
@@ -7,4 +8,3 @@
  </ul>
  <br/>
 {%endblock%}
-
diff --git a/pgcommitfest/commitfest/tests/test_ics_feed.py b/pgcommitfest/commitfest/tests/test_ics_feed.py
new file mode 100644
index 00000000..b0382450
--- /dev/null
+++ b/pgcommitfest/commitfest/tests/test_ics_feed.py
@@ -0,0 +1,40 @@
+"""
+Tests for the /commitfests.ics calendar feed.
+"""
+
+from __future__ import annotations
+
+from datetime import timedelta
+from typing import TYPE_CHECKING
+
+import pytest
+from icalendar import Calendar
+
+if TYPE_CHECKING:
+    from pgcommitfest.commitfest.models import CommitFest
+
+pytestmark = pytest.mark.django_db
+
+
+def test_commitfests_ics(client, commitfests: dict[str, CommitFest]):
+    """
+    Every non-draft commitfest, regardless of status, shows up as an all-day
+    VEVENT with DTEND being the day after enddate (exclusive).
+    """
+    commitfests = {k: cf for k, cf in commitfests.items() if not cf.draft}
+
+    response = client.get("/commitfests.ics")
+    assert response.status_code == 200
+    assert response["Content-Type"] == "text/calendar; charset=utf-8"
+
+    events = Calendar.from_ical(response.content).walk("VEVENT")
+    assert len(events) == len(commitfests)
+    events_by_uid = {str(event.uid): event for event in events}
+
+    for cf in commitfests.values():
+        event = events_by_uid[f"commitfest-{cf.name}@commitfest.postgresql.org"]
+        assert event.summary == f"Commitfest {cf.name}"
+        assert event.url == f"https://commitfest.postgresql.org/{cf.pk}/"
+        assert event.description == f"Status: {cf.statusstring}"
+        assert event.start == cf.startdate
+        assert event.end == cf.enddate + timedelta(days=1)
diff --git a/pgcommitfest/commitfest/views.py b/pgcommitfest/commitfest/views.py
index b6659ac8..a484d49b 100644
--- a/pgcommitfest/commitfest/views.py
+++ b/pgcommitfest/commitfest/views.py
@@ -6,6 +6,7 @@
 from django.db.models import Count, Q
 from django.http import (
     Http404,
+    HttpRequest,
     HttpResponse,
     HttpResponseForbidden,
     HttpResponsePermanentRedirect,
@@ -27,7 +28,7 @@
 from pgcommitfest.userprofile.util import UserWrapper
 
 from .ajax import _archivesAPI, doAttachThread, refresh_single_thread
-from .feeds import ActivityFeed
+from .feeds import ActivityFeed, calendar
 from .forms import (
     BulkEmailForm,
     CommitFestFilterForm,
@@ -228,6 +229,19 @@ def help(request):
     )
 
 
+def commitfests_ics(_: HttpRequest) -> HttpResponse:
+    """
+    Calendar feed of all non-draft commitfests in iCalendar format (RFC 5545).
+    """
+    commitfests = CommitFest.objects.filter(draft=False).order_by("startdate")
+
+    response = HttpResponse(
+        calendar(commitfests).to_ical(), content_type="text/calendar; charset=utf-8"
+    )
+    response["Content-Disposition"] = 'inline; filename="commitfests.ics"'
+    return response
+
+
 def activity(request, cfid=None, rss=None):
     # Number of notes to fetch
     if rss:
diff --git a/pgcommitfest/urls.py b/pgcommitfest/urls.py
index 3e0aaa46..de80e32c 100644
--- a/pgcommitfest/urls.py
+++ b/pgcommitfest/urls.py
@@ -24,6 +24,7 @@
     re_path(r"^commitfest_history/$", views.commitfest_history_legacy_redirect),
     re_path(r"^me/$", views.me_legacy_redirect),
     re_path(r"^archive/$", views.archive),
+    re_path(r"^commitfests\.ics$", views.commitfests_ics),
     re_path(r"^activity(?P<rss>\.rss)?/", views.activity),
     re_path(r"^(\d+)/$", views.commitfest),
     re_path(r"^(open|inprogress|current|draft)/(.*)$", views.redir),
diff --git a/pyproject.toml b/pyproject.toml
index 4ca7a0f6..c3a6a178 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -6,6 +6,7 @@ readme = "README.md"
 license = "PostgreSQL"
 dependencies = [
     "django>=5.2,<6.0",
+    "icalendar",
     "psycopg2",
     "simplejson",
     "requests",