diff --git a/crates/ascend/src/pages/wall.rs b/crates/ascend/src/pages/wall.rs
index 46c2b2e..3f18733 100644
--- a/crates/ascend/src/pages/wall.rs
+++ b/crates/ascend/src/pages/wall.rs
@@ -45,6 +45,7 @@ use crate::server_functions;
 use leptos::Params;
 use leptos::prelude::*;
 use leptos_router::params::Params;
+use std::collections::BTreeSet;
 use web_sys::MouseEvent;
 
 #[derive(Params, PartialEq, Clone)]
@@ -122,6 +123,19 @@ fn WithWall(#[prop(into)] wall: Signal<models::Wall>) -> impl IntoView {
 
     let (problem_uid, set_problem_uid) = leptos_router::hooks::query_signal::<models::ProblemUid>("problem");
 
+    // Filter
+    let (filter_holds, set_filter_holds) = signal(BTreeSet::new());
+    let filter_add_hold = move |hold_pos: models::HoldPosition| {
+        set_filter_holds.update(move |set| {
+            set.insert(hold_pos);
+        });
+    };
+    let filter_remove_hold = move |hold_pos: models::HoldPosition| {
+        set_filter_holds.update(move |set| {
+            set.remove(&hold_pos);
+        });
+    };
+
     let problem = crate::resources::problem_by_uid_optional(wall_uid, problem_uid.into());
     let user_interaction = crate::resources::user_interaction(wall_uid, problem_uid.into());
 
@@ -140,6 +154,14 @@ fn WithWall(#[prop(into)] wall: Signal<models::Wall>) -> impl IntoView {
     // merge outer option (resource hasn't resolved yet) with inner option (there is no problem for the wall)
     let problem_signal = Signal::derive(move || problem.get().transpose().map(Option::flatten));
 
+    let on_click_hold = move |hold_position: models::HoldPosition| {
+        set_filter_holds.update(|set| {
+            if !set.remove(&hold_position) {
+                set.insert(hold_position);
+            }
+        });
+    };
+
     let grid = {
         let wall = wall.clone();
         view! {
@@ -151,7 +173,9 @@ fn WithWall(#[prop(into)] wall: Signal<models::Wall>) -> impl IntoView {
                         Suspend::new(async move {
                             let wall = wall.clone();
                             tracing::info!("executing grid suspend");
-                            let view = view! { <Grid wall=wall.get() problem=problem_signal /> };
+                            let view = view! {
+                                <Grid wall=wall.get() problem=problem_signal on_click_hold />
+                            };
                             Ok::<_, ServerFnError>(view)
                         })
                     }
@@ -160,12 +184,25 @@ fn WithWall(#[prop(into)] wall: Signal<models::Wall>) -> impl IntoView {
         }
     };
 
+    let filter = move || {
+        let mut cells = vec![];
+        for hold_pos in filter_holds.get() {
+            let w = &*wall.read();
+            if let Some(hold) = w.holds.get(&hold_pos).cloned() {
+                let v = view! { <Hold hold /> };
+                cells.push(v);
+            }
+        }
+
+        view! { <div class="grid grid-cols-4 gap-2">{cells}</div> }
+    };
+
     view! {
         <div class="inline-grid grid-cols-1 gap-8 md:grid-cols-[auto,1fr]">
             <div>{grid}</div>
 
-            <div class="flex flex-col">
-                <Section title="Filter">{}</Section>
+            <div class="flex flex-col max-w-screen-sm">
+                <Section title="Filter">{filter}</Section>
 
                 <Separator />
 
@@ -369,14 +406,27 @@ fn AttemptRadio(
 
 #[component]
 #[tracing::instrument(skip_all)]
-fn Grid(wall: models::Wall, #[prop(into)] problem: Signal<Result<Option<models::Problem>, ServerFnError>>) -> impl IntoView {
+fn Grid(
+    wall: models::Wall,
+    #[prop(into)] problem: Signal<Result<Option<models::Problem>, ServerFnError>>,
+    on_click_hold: impl Fn(models::HoldPosition) + 'static,
+) -> impl IntoView {
     tracing::debug!("Enter");
 
+    let on_click_hold = std::rc::Rc::new(on_click_hold);
+
     let mut cells = vec![];
     for (&hold_position, hold) in &wall.holds {
         let role = move || problem.get().map(|o| o.and_then(|p| p.holds.get(&hold_position).copied()));
         let role = Signal::derive(role);
-        let cell = view! { <Hold role hold=hold.clone() /> };
+
+        let on_click = {
+            let on_click_hold = std::rc::Rc::clone(&on_click_hold);
+            move |_| {
+                on_click_hold(hold_position);
+            }
+        };
+        let cell = view! { <Hold on:click=on_click role hold=hold.clone() /> };
         cells.push(cell);
     }
     let grid_classes = format!("grid grid-rows-{} grid-cols-{} gap-1", wall.rows, wall.cols,);
@@ -393,13 +443,20 @@ fn Grid(wall: models::Wall, #[prop(into)] problem: Signal<Result<Option<models::
 // TODO: refactor this to use the Problem component
 #[component]
 #[tracing::instrument(skip_all)]
-fn Hold(hold: models::Hold, role: Signal<Result<Option<HoldRole>, ServerFnError>>) -> impl IntoView {
+fn Hold(
+    hold: models::Hold,
+
+    #[prop(optional)]
+    #[prop(into)]
+    role: Option<Signal<Result<Option<HoldRole>, ServerFnError>>>,
+) -> impl IntoView {
     tracing::trace!("Enter");
 
     move || {
-        let role = role.get()?;
+        let mut class = "bg-sky-100 aspect-square rounded hover:brightness-125".to_string();
+        if let Some(role) = role {
+            let role = role.get()?;
 
-        let class = {
             let role_classes = match role {
                 Some(HoldRole::Start) => Some("outline outline-offset-2 outline-green-500"),
                 Some(HoldRole::Normal) => Some("outline outline-offset-2 outline-blue-500"),
@@ -407,13 +464,11 @@ fn Hold(hold: models::Hold, role: Signal<Result<Option<HoldRole>, ServerFnError>
                 Some(HoldRole::End) => Some("outline outline-offset-2 outline-red-500"),
                 None => Some("brightness-50"),
             };
-            let mut s = "bg-sky-100 aspect-square rounded hover:brightness-125".to_string();
             if let Some(c) = role_classes {
-                s.push(' ');
-                s.push_str(c);
+                class.push(' ');
+                class.push_str(c);
             }
-            s
-        };
+        }
 
         let img = hold.image.as_ref().map(|img| {
             let srcset = img.srcset();