diff --git a/frontend/src/app/pages/agenda/agenda.html b/frontend/src/app/pages/agenda/agenda.html
index a5a4d01..277b869 100644
--- a/frontend/src/app/pages/agenda/agenda.html
+++ b/frontend/src/app/pages/agenda/agenda.html
@@ -11,6 +11,13 @@
           <h3>Agenda</h3>
           <small>{{calendarEvents.length}} évènements</small>
         </div>
+        <div class="sidebar-filters">
+          <app-what-filter 
+            [label]="'Filtrer par type d\'événement'"
+            [available]="availableWhatTypes"
+            [selected]="selectedWhatFilter"
+            (selectedChange)="onWhatFilterChange($event)"></app-what-filter>
+        </div>
         <div class="day-groups">
           @for (group of groupedEvents; track group.dateKey) {
             <div class="day-group">
@@ -41,7 +48,7 @@
 
       <main class="agenda-main">
         <app-calendar 
-          [events]="calendarEvents"
+          [events]="filteredCalendarEvents"
           (eventClick)="onEventClick($event)"
           (dateClick)="onDateClick($event)">
         </app-calendar>
diff --git a/frontend/src/app/pages/agenda/agenda.ts b/frontend/src/app/pages/agenda/agenda.ts
index 75b3ab4..c5b6f06 100644
--- a/frontend/src/app/pages/agenda/agenda.ts
+++ b/frontend/src/app/pages/agenda/agenda.ts
@@ -5,6 +5,7 @@ import { OedbApi } from '../../services/oedb-api';
 import { EditForm } from '../../forms/edit-form/edit-form';
 import { CalendarComponent, CalendarEvent } from './calendar/calendar';
 import oedb from '../../../oedb-types';
+import { WhatFilterComponent } from '../../shared/what-filter/what-filter';
 
 interface OedbEvent {
   id: string;
@@ -27,7 +28,7 @@ interface OedbEvent {
 @Component({
   selector: 'app-agenda',
   standalone: true,
-  imports: [CommonModule, FormsModule, EditForm, CalendarComponent],
+  imports: [CommonModule, FormsModule, EditForm, CalendarComponent, WhatFilterComponent],
   templateUrl: './agenda.html',
   styleUrl: './agenda.scss'
 })
@@ -35,11 +36,15 @@ export class Agenda implements OnInit {
   private oedbApi = inject(OedbApi);
   
   events: OedbEvent[] = [];
+  filteredEvents: OedbEvent[] = [];
   calendarEvents: CalendarEvent[] = [];
+  filteredCalendarEvents: CalendarEvent[] = [];
   selectedEvent: OedbEvent | null = null;
   isLoading = false;
 
   groupedEvents: Array<{ dateKey: string; date: Date; items: OedbEvent[] }> = [];
+  availableWhatTypes: string[] = [];
+  selectedWhatFilter = '';
 
   ngOnInit() {
     this.loadEvents();
@@ -61,14 +66,15 @@ export class Agenda implements OnInit {
 
     this.oedbApi.getEvents(params).subscribe((response: any) => {
       this.events = Array.isArray(response?.features) ? response.features : [];
-      this.convertToCalendarEvents();
-      this.buildGroupedEvents();
+      this.updateAvailableWhatTypes();
+      this.applyWhatFilter();
       this.isLoading = false;
     });
   }
 
   convertToCalendarEvents() {
-    this.calendarEvents = this.events.map(event => {
+    const source = this.filteredEvents.length ? this.filteredEvents : this.events;
+    this.calendarEvents = source.map(event => {
       const startDate = this.parseEventDate(event.properties.start || event.properties.when);
       const endDate = event.properties.stop ? this.parseEventDate(event.properties.stop) : null;
 
@@ -83,6 +89,7 @@ export class Agenda implements OnInit {
         properties: event.properties
       };
     });
+    this.filteredCalendarEvents = this.calendarEvents;
   }
 
   parseEventDate(dateString: string | undefined): Date {
@@ -132,6 +139,29 @@ export class Agenda implements OnInit {
   }
 
   // Sidebar helpers
+  updateAvailableWhatTypes() {
+    const set = new Set<string>();
+    for (const e of this.events) {
+      const w = e?.properties?.what;
+      if (w) set.add(w);
+    }
+    this.availableWhatTypes = Array.from(set).sort();
+  }
+
+  applyWhatFilter() {
+    if (this.selectedWhatFilter) {
+      this.filteredEvents = this.events.filter(e => e?.properties?.what === this.selectedWhatFilter);
+    } else {
+      this.filteredEvents = [...this.events];
+    }
+    this.convertToCalendarEvents();
+    this.buildGroupedEvents();
+  }
+
+  onWhatFilterChange(value: string) {
+    this.selectedWhatFilter = value || '';
+    this.applyWhatFilter();
+  }
   private getEventStartDate(ev: OedbEvent): Date {
     const ds = ev.properties.start || ev.properties.when;
     return this.parseEventDate(ds);
diff --git a/frontend/src/app/pages/home/home.html b/frontend/src/app/pages/home/home.html
index ae4d237..a29457c 100644
--- a/frontend/src/app/pages/home/home.html
+++ b/frontend/src/app/pages/home/home.html
@@ -52,13 +52,7 @@
       <input class="input" type="text" placeholder="Rechercher..." [(ngModel)]="searchText" (ngModelChange)="onSearchChange()">
       
       <div class="control-group">
-        <label>Filtrer par type d'événement</label>
-        <select class="input" [(ngModel)]="selectedWhatFilter" (ngModelChange)="onWhatFilterChange()">
-        <option value="">Tous les types</option>
-        @for (whatType of availableWhatTypes; track whatType) {
-          <option [value]="whatType">{{whatType}}</option>
-          }
-        </select>
+        <app-what-filter [label]="'Filtrer par type d\'événement'" [available]="availableWhatTypes" [selected]="selectedWhatFilter" (selectedChange)="selectedWhatFilter = $event; onWhatFilterChange()"></app-what-filter>
       </div>
 
 
diff --git a/frontend/src/app/pages/home/home.ts b/frontend/src/app/pages/home/home.ts
index bd50e86..dabb1df 100644
--- a/frontend/src/app/pages/home/home.ts
+++ b/frontend/src/app/pages/home/home.ts
@@ -8,6 +8,7 @@ import { OedbApi } from '../../services/oedb-api';
 import { UnlocatedEvents } from '../../shared/unlocated-events/unlocated-events';
 import { OsmAuth } from '../../services/osm-auth';
 import { Osm } from '../../forms/osm/osm';
+import { WhatFilterComponent } from '../../shared/what-filter/what-filter';
 @Component({
   selector: 'app-home',
   standalone: true,
@@ -17,7 +18,8 @@ import { Osm } from '../../forms/osm/osm';
     UnlocatedEvents,
     EditForm,
     Osm,
-    FormsModule
+    FormsModule,
+    WhatFilterComponent
   ],
   templateUrl: './home.html',
   styleUrl: './home.scss'
diff --git a/frontend/src/app/shared/what-filter/what-filter.ts b/frontend/src/app/shared/what-filter/what-filter.ts
new file mode 100644
index 0000000..babd262
--- /dev/null
+++ b/frontend/src/app/shared/what-filter/what-filter.ts
@@ -0,0 +1,44 @@
+import { Component, EventEmitter, Input, Output } from '@angular/core';
+import { CommonModule } from '@angular/common';
+import { FormsModule } from '@angular/forms';
+
+@Component({
+  selector: 'app-what-filter',
+  standalone: true,
+  imports: [CommonModule, FormsModule],
+  template: `
+    <div class="what-filter">
+      <label *ngIf="label" class="filter-label">{{label}}</label>
+      <select class="input" [(ngModel)]="internalSelected" (ngModelChange)="onSelectedChange($event)">
+        <option value="">Tous les types</option>
+        <option *ngFor="let what of available" [value]="what">{{what}}</option>
+      </select>
+    </div>
+  `,
+  styles: [`
+    .what-filter { display: flex; flex-direction: column; gap: 6px; }
+    .filter-label { font-size: 0.9rem; color: #374151; }
+    .input { padding: 8px 10px; border: 1px solid #dee2e6; border-radius: 4px; font-size: 0.9rem; }
+    .input:focus { outline: none; border-color: #3498db; }
+  `]
+})
+export class WhatFilterComponent {
+  @Input() available: string[] = [];
+  @Input() label: string | null = null;
+
+  @Input() set selected(val: string) {
+    this.internalSelected = val || '';
+  }
+  get selected(): string { return this.internalSelected; }
+
+  @Output() selectedChange = new EventEmitter<string>();
+
+  internalSelected = '';
+
+  onSelectedChange(value: string) {
+    this.internalSelected = value || '';
+    this.selectedChange.emit(this.internalSelected);
+  }
+}
+
+