diff --git a/Cargo.lock b/Cargo.lock
index ba16073..b34e1dd 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3152,6 +3152,7 @@ dependencies = [
  "headers",
  "hex",
  "http",
+ "itertools 0.14.0",
  "mime_guess",
  "percent-encoding",
  "rand 0.9.2",
@@ -3160,6 +3161,7 @@ dependencies = [
  "rustical_oidc",
  "rustical_store",
  "serde",
+ "serde_json",
  "thiserror 2.0.17",
  "tokio",
  "tower",
@@ -3168,6 +3170,7 @@ dependencies = [
  "tracing",
  "url",
  "uuid",
+ "vtimezones-rs",
 ]
 
 [[package]]
diff --git a/crates/frontend/Cargo.toml b/crates/frontend/Cargo.toml
index 2a589b9..009de98 100644
--- a/crates/frontend/Cargo.toml
+++ b/crates/frontend/Cargo.toml
@@ -39,3 +39,6 @@ headers.workspace = true
 tower-sessions.workspace = true
 percent-encoding.workspace = true
 tower-http = { workspace = true, optional = true }
+vtimezones-rs.workspace = true
+serde_json.workspace = true
+itertools.workspace = true
diff --git a/crates/frontend/js-components/lib/create-calendar-form.ts b/crates/frontend/js-components/lib/create-calendar-form.ts
index 516987e..1bbbc3d 100644
--- a/crates/frontend/js-components/lib/create-calendar-form.ts
+++ b/crates/frontend/js-components/lib/create-calendar-form.ts
@@ -7,6 +7,11 @@ import { escapeXml } from ".";
 export class CreateCalendarForm extends LitElement {
   constructor() {
     super()
+    this.fetchTimezones()
+  }
+
+  async fetchTimezones() {
+    this.timezones = await getTimezones()
   }
 
   protected override createRenderRoot() {
@@ -36,6 +41,8 @@ export class CreateCalendarForm extends LitElement {
 
   dialog: Ref<HTMLDialogElement> = createRef()
   form: Ref<HTMLFormElement> = createRef()
+  @property()
+  timezones: Array<String> = []
 
   override render() {
     return html`
@@ -65,7 +72,12 @@ export class CreateCalendarForm extends LitElement {
           <br>
           <label>
             Timezone (optional)
-            <input type="text" name="timezone" .value=${this.timezone_id} @change=${e => this.timezone_id = e.target.value} />
+            <select name="timezone" .value=${this.timezone_id} @change=${e => this.timezone_id = e.target.value}>
+              <option value="">No timezone</option>
+              ${this.timezones.map(timezone => html`
+                <option value=${timezone} ?selected=${timezone === this.timezone_id}>${timezone}</option>
+              `)}
+            </select>
           </label>
           <br>
           <label>
diff --git a/crates/frontend/js-components/lib/edit-calendar-form.ts b/crates/frontend/js-components/lib/edit-calendar-form.ts
index f835b1b..2f41c63 100644
--- a/crates/frontend/js-components/lib/edit-calendar-form.ts
+++ b/crates/frontend/js-components/lib/edit-calendar-form.ts
@@ -2,11 +2,17 @@ import { html, LitElement } from "lit";
 import { customElement, property } from "lit/decorators.js";
 import { Ref, createRef, ref } from 'lit/directives/ref.js';
 import { escapeXml } from ".";
+import { getTimezones } from "./timezones.ts";
 
 @customElement("edit-calendar-form")
 export class EditCalendarForm extends LitElement {
   constructor() {
     super()
+    this.fetchTimezones()
+  }
+
+  async fetchTimezones() {
+    this.timezones = await getTimezones()
   }
 
   protected override createRenderRoot() {
@@ -36,7 +42,8 @@ export class EditCalendarForm extends LitElement {
 
   dialog: Ref<HTMLDialogElement> = createRef()
   form: Ref<HTMLFormElement> = createRef()
-
+  @property()
+  timezones: Array<String> = []
 
   override render() {
     return html`
@@ -51,7 +58,12 @@ export class EditCalendarForm extends LitElement {
           <br>
           <label>
             Timezone (optional)
-            <input type="text" name="timezone" .value=${this.timezone_id} @change=${e => this.timezone_id = e.target.value} />
+            <select name="timezone" .value=${this.timezone_id} @change=${e => this.timezone_id = e.target.value}>
+              <option value="">No timezone</option>
+              ${this.timezones.map(timezone => html`
+                <option value=${timezone} ?selected=${timezone === this.timezone_id}>${timezone}</option>
+              `)}
+            </select>
           </label>
           <br>
           <label>
diff --git a/crates/frontend/js-components/lib/timezones.ts b/crates/frontend/js-components/lib/timezones.ts
new file mode 100644
index 0000000..41850e8
--- /dev/null
+++ b/crates/frontend/js-components/lib/timezones.ts
@@ -0,0 +1,12 @@
+let timezonesPromise = null
+export async function getTimezones() {
+  timezonesPromise ||= new Promise(async (resolve, reject) => {
+    try {
+      let response = await fetch('/frontend/_timezones.json')
+      resolve(await response.json())
+    } catch (e) {
+      reject(e)
+    }
+  })
+  return await timezonesPromise
+}
diff --git a/crates/frontend/public/assets/js/create-calendar-form.mjs b/crates/frontend/public/assets/js/create-calendar-form.mjs
index dc49ad1..816642a 100644
--- a/crates/frontend/public/assets/js/create-calendar-form.mjs
+++ b/crates/frontend/public/assets/js/create-calendar-form.mjs
@@ -27,6 +27,11 @@ let CreateCalendarForm = class extends i {
     this.components = /* @__PURE__ */ new Set();
     this.dialog = e();
     this.form = e();
+    this.timezones = [];
+    this.fetchTimezones();
+  }
+  async fetchTimezones() {
+    this.timezones = await getTimezones();
   }
   createRenderRoot() {
     return this;
@@ -59,7 +64,12 @@ let CreateCalendarForm = class extends i {
           <br>
           <label>
             Timezone (optional)
-            <input type="text" name="timezone" .value=${this.timezone_id} @change=${(e2) => this.timezone_id = e2.target.value} />
+            <select name="timezone" .value=${this.timezone_id} @change=${(e2) => this.timezone_id = e2.target.value}>
+              <option value="">No timezone</option>
+              ${this.timezones.map((timezone) => x`
+                <option value=${timezone} ?selected=${timezone === this.timezone_id}>${timezone}</option>
+              `)}
+            </select>
           </label>
           <br>
           <label>
@@ -179,6 +189,9 @@ __decorateClass([
 __decorateClass([
   n$1()
 ], CreateCalendarForm.prototype, "components", 2);
+__decorateClass([
+  n$1()
+], CreateCalendarForm.prototype, "timezones", 2);
 CreateCalendarForm = __decorateClass([
   t("create-calendar-form")
 ], CreateCalendarForm);
diff --git a/crates/frontend/public/assets/js/edit-calendar-form.mjs b/crates/frontend/public/assets/js/edit-calendar-form.mjs
index 8fbad5e..256d594 100644
--- a/crates/frontend/public/assets/js/edit-calendar-form.mjs
+++ b/crates/frontend/public/assets/js/edit-calendar-form.mjs
@@ -2,6 +2,18 @@ import { i, x } from "./lit-DkXrt_Iv.mjs";
 import { n as n$1, t } from "./property-B8WoKf1Y.mjs";
 import { e, n } from "./ref-BwbQvJBB.mjs";
 import { e as escapeXml } from "./index-_IB1wMbZ.mjs";
+let timezonesPromise = null;
+async function getTimezones() {
+  timezonesPromise ||= new Promise(async (resolve, reject) => {
+    try {
+      let response = await fetch("/frontend/_timezones.json");
+      resolve(await response.json());
+    } catch (e2) {
+      reject(e2);
+    }
+  });
+  return await timezonesPromise;
+}
 var __defProp = Object.defineProperty;
 var __getOwnPropDesc = Object.getOwnPropertyDescriptor;
 var __decorateClass = (decorators, target, key, kind) => {
@@ -22,6 +34,11 @@ let EditCalendarForm = class extends i {
     this.components = /* @__PURE__ */ new Set();
     this.dialog = e();
     this.form = e();
+    this.timezones = [];
+    this.fetchTimezones();
+  }
+  async fetchTimezones() {
+    this.timezones = await getTimezones();
   }
   createRenderRoot() {
     return this;
@@ -39,7 +56,12 @@ let EditCalendarForm = class extends i {
           <br>
           <label>
             Timezone (optional)
-            <input type="text" name="timezone" .value=${this.timezone_id} @change=${(e2) => this.timezone_id = e2.target.value} />
+            <select name="timezone" .value=${this.timezone_id} @change=${(e2) => this.timezone_id = e2.target.value}>
+              <option value="">No timezone</option>
+              ${this.timezones.map((timezone) => x`
+                <option value=${timezone} ?selected=${timezone === this.timezone_id}>${timezone}</option>
+              `)}
+            </select>
           </label>
           <br>
           <label>
@@ -150,6 +172,9 @@ __decorateClass([
     }
   })
 ], EditCalendarForm.prototype, "components", 2);
+__decorateClass([
+  n$1()
+], EditCalendarForm.prototype, "timezones", 2);
 EditCalendarForm = __decorateClass([
   t("edit-calendar-form")
 ], EditCalendarForm);
diff --git a/crates/frontend/public/templates/components/sections/calendars_section.html b/crates/frontend/public/templates/components/sections/calendars_section.html
index afbbee6..02c39c6 100644
--- a/crates/frontend/public/templates/components/sections/calendars_section.html
+++ b/crates/frontend/public/templates/components/sections/calendars_section.html
@@ -85,4 +85,3 @@
 {% endif %}
 <create-calendar-form user="{{ user.id }}"></create-calendar-form>
 <import-calendar-form user="{{ user.id }}"></import-calendar-form>
-
diff --git a/crates/frontend/src/lib.rs b/crates/frontend/src/lib.rs
index 91bebd2..cee1d06 100644
--- a/crates/frontend/src/lib.rs
+++ b/crates/frontend/src/lib.rs
@@ -33,6 +33,7 @@ use crate::routes::{
     app_token::{route_delete_app_token, route_post_app_token},
     calendar::{route_calendar, route_calendar_restore},
     login::{route_get_login, route_post_login, route_post_logout},
+    timezones::route_timezones,
     user::{route_get_home, route_root, route_user_named},
 };
 #[cfg(not(feature = "dev"))]
@@ -79,7 +80,11 @@ pub fn frontend_router<AP: AuthenticationProvider, CS: CalendarStore, AS: Addres
         .route("/", get(route_root))
         .nest("/user", user_router)
         .route("/login", get(route_get_login).post(route_post_login::<AP>))
-        .route("/logout", post(route_post_logout));
+        .route("/logout", post(route_post_logout))
+        .route(
+            "/_timezones.json",
+            get(route_timezones).head(route_timezones),
+        );
 
     #[cfg(not(feature = "dev"))]
     let mut router = router.route_service("/assets/{*file}", EmbedService::<Assets>::default());
diff --git a/crates/frontend/src/routes/mod.rs b/crates/frontend/src/routes/mod.rs
index f3ecc12..9a67a97 100644
--- a/crates/frontend/src/routes/mod.rs
+++ b/crates/frontend/src/routes/mod.rs
@@ -4,4 +4,5 @@ pub mod app_token;
 pub mod calendar;
 pub mod calendars;
 pub mod login;
+pub mod timezones;
 pub mod user;
diff --git a/crates/frontend/src/routes/timezones.rs b/crates/frontend/src/routes/timezones.rs
new file mode 100644
index 0000000..b4c75ed
--- /dev/null
+++ b/crates/frontend/src/routes/timezones.rs
@@ -0,0 +1,30 @@
+use axum::response::{IntoResponse, Response};
+use headers::{CacheControl, ContentType, HeaderMapExt};
+use http::{HeaderMap, HeaderValue, Method};
+use itertools::Itertools;
+use std::{sync::LazyLock, time::Duration};
+
+static VTIMEZONES_JSON: LazyLock<String> = LazyLock::new(|| {
+    serde_json::to_string(
+        &vtimezones_rs::VTIMEZONES
+            .keys()
+            .sorted()
+            .collect::<Vec<_>>(),
+    )
+    .unwrap()
+});
+
+pub async fn route_timezones(method: Method) -> Response {
+    let mut headers = HeaderMap::new();
+    headers.typed_insert(ContentType::json());
+    headers.insert(
+        "ETag",
+        HeaderValue::from_static(vtimezones_rs::IANA_TZDB_VERSION),
+    );
+    headers.typed_insert(CacheControl::new().with_max_age(Duration::from_hours(2)));
+
+    if method == Method::HEAD {
+        return headers.into_response();
+    }
+    (headers, VTIMEZONES_JSON.as_str()).into_response()
+}