diff --git a/src/App.jsx b/src/App.jsx
index 8bfad1a..b1ea55d 100644
--- a/src/App.jsx
+++ b/src/App.jsx
@@ -6,6 +6,7 @@ import { decodePolyline } from './utils/decode'
 import MapView from './components/MapView'
 import Panel from './components/Panel'
 import PlaceDetail from './components/PlaceDetail'
+import LayerControl from './components/LayerControl'
 
 export default function App() {
   const mapViewRef = useRef(null)
@@ -106,6 +107,7 @@ export default function App() {
       <MapView ref={mapViewRef} />
       <Panel onManeuverClick={handleManeuverClick} />
       <PlaceDetail />
+      <LayerControl mapRef={mapViewRef} />
     </div>
   )
 }
diff --git a/src/components/LayerControl.jsx b/src/components/LayerControl.jsx
new file mode 100644
index 0000000..52f8dec
--- /dev/null
+++ b/src/components/LayerControl.jsx
@@ -0,0 +1,126 @@
+import { useState, useEffect, useRef } from 'react'
+import { Layers } from 'lucide-react'
+import { hasFeature, getConfig } from '../config'
+
+const STORAGE_KEY = 'navi-layer-prefs'
+
+function loadPrefs() {
+  try {
+    const raw = localStorage.getItem(STORAGE_KEY)
+    if (raw) return JSON.parse(raw)
+  } catch {}
+  return null
+}
+
+function savePrefs(prefs) {
+  localStorage.setItem(STORAGE_KEY, JSON.stringify(prefs))
+}
+
+export default function LayerControl({ mapRef }) {
+  const [open, setOpen] = useState(false)
+  const [hillshade, setHillshade] = useState(false)
+  const [traffic, setTraffic] = useState(false)
+  const panelRef = useRef(null)
+
+  // Initialize from localStorage or defaults on mount
+  useEffect(() => {
+    const saved = loadPrefs()
+    const hsAvailable = hasFeature('has_hillshade')
+    const trAvailable = hasFeature('has_traffic_overlay')
+
+    if (saved) {
+      setHillshade(hsAvailable && (saved.hillshade ?? true))
+      setTraffic(trAvailable && (saved.traffic ?? false))
+    } else {
+      // Defaults: hillshade ON if available, traffic OFF
+      setHillshade(hsAvailable)
+      setTraffic(false)
+    }
+  }, [])
+
+  // Apply layers when prefs change
+  useEffect(() => {
+    const map = mapRef?.current?.getMap?.()
+    if (!map || !map.isStyleLoaded()) return
+
+    if (hillshade && hasFeature('has_hillshade')) {
+      mapRef.current.addHillshadeLayer?.()
+    } else {
+      mapRef.current.removeHillshadeLayer?.()
+    }
+    savePrefs({ hillshade, traffic })
+  }, [hillshade, mapRef])
+
+  useEffect(() => {
+    const map = mapRef?.current?.getMap?.()
+    if (!map || !map.isStyleLoaded()) return
+
+    if (traffic && hasFeature('has_traffic_overlay')) {
+      mapRef.current.addTrafficLayer?.()
+    } else {
+      mapRef.current.removeTrafficLayer?.()
+    }
+    savePrefs({ hillshade, traffic })
+  }, [traffic, mapRef])
+
+  // Close on outside click
+  useEffect(() => {
+    if (!open) return
+    function handleClick(e) {
+      if (panelRef.current && !panelRef.current.contains(e.target)) {
+        setOpen(false)
+      }
+    }
+    document.addEventListener('mousedown', handleClick)
+    return () => document.removeEventListener('mousedown', handleClick)
+  }, [open])
+
+  const showHillshade = hasFeature('has_hillshade')
+  const showTraffic = hasFeature('has_traffic_overlay')
+
+  // Don't render if no overlay features available
+  if (!showHillshade && !showTraffic) return null
+
+  return (
+    <div ref={panelRef} className="layer-control">
+      <button
+        className="layer-control-btn"
+        onClick={() => setOpen((v) => !v)}
+        title="Map layers"
+        aria-label="Toggle map layers"
+      >
+        <Layers size={18} />
+      </button>
+
+      {open && (
+        <div className="layer-control-popover">
+          <div className="layer-control-header">Layers</div>
+
+          {showHillshade && (
+            <label className="layer-control-item">
+              <span className="layer-control-label">Hillshade</span>
+              <input
+                type="checkbox"
+                className="layer-control-toggle"
+                checked={hillshade}
+                onChange={(e) => setHillshade(e.target.checked)}
+              />
+            </label>
+          )}
+
+          {showTraffic && (
+            <label className="layer-control-item">
+              <span className="layer-control-label">Traffic</span>
+              <input
+                type="checkbox"
+                className="layer-control-toggle"
+                checked={traffic}
+                onChange={(e) => setTraffic(e.target.checked)}
+              />
+            </label>
+          )}
+        </div>
+      )}
+    </div>
+  )
+}
diff --git a/src/components/MapView.jsx b/src/components/MapView.jsx
index c5154b9..3c086b2 100644
--- a/src/components/MapView.jsx
+++ b/src/components/MapView.jsx
@@ -6,10 +6,14 @@ import { layers, namedTheme } from 'protomaps-themes-base'
 import { useStore } from '../store'
 import { decodePolyline } from '../utils/decode'
 import { fetchReverse } from '../api'
-import { getConfig } from '../config'
+import { getConfig, hasFeature } from '../config'
 
 const ROUTE_SOURCE = 'route-source'
 const ROUTE_LAYER_PREFIX = 'route-layer-'
+const HILLSHADE_SOURCE = 'hillshade-dem'
+const HILLSHADE_LAYER = 'hillshade-layer'
+const TRAFFIC_SOURCE = 'traffic-tiles'
+const TRAFFIC_LAYER = 'traffic-layer'
 
 /** Build a full MapLibre style object for the given theme */
 function buildStyle(themeName) {
@@ -37,6 +41,83 @@ const CHEVRON_SVG = `<svg width="16" height="16" viewBox="0 0 16 16" xmlns="http
   <path d="M8 1 L14 13 L8 10 L2 13 Z" fill="var(--accent)" stroke="var(--bg-raised)" stroke-width="1.5" stroke-linejoin="round"/>
 </svg>`
 
+/** Add hillshade raster-dem source + layer to the map */
+function addHillshade(map) {
+  if (!map || map.getSource(HILLSHADE_SOURCE)) return
+  const config = getConfig()
+  const hs = config?.tileset_hillshade
+  if (!hs?.url) return
+
+  map.addSource(HILLSHADE_SOURCE, {
+    type: 'raster-dem',
+    url: `pmtiles://${hs.url}`,
+    encoding: hs.encoding || 'terrarium',
+    tileSize: 256,
+    maxzoom: hs.max_zoom || 12,
+  })
+
+  // Insert below the first symbol/label layer for proper z-ordering
+  let beforeId = undefined
+  for (const layer of map.getStyle().layers) {
+    if (layer.type === 'symbol') {
+      beforeId = layer.id
+      break
+    }
+  }
+
+  map.addLayer({
+    id: HILLSHADE_LAYER,
+    type: 'hillshade',
+    source: HILLSHADE_SOURCE,
+    paint: {
+      'hillshade-exaggeration': 0.5,
+      'hillshade-illumination-direction': 315,
+      'hillshade-shadow-color': '#000000',
+      'hillshade-highlight-color': '#ffffff',
+    },
+  }, beforeId)
+}
+
+/** Remove hillshade layer + source */
+function removeHillshade(map) {
+  if (!map) return
+  if (map.getLayer(HILLSHADE_LAYER)) map.removeLayer(HILLSHADE_LAYER)
+  if (map.getSource(HILLSHADE_SOURCE)) map.removeSource(HILLSHADE_SOURCE)
+}
+
+/** Add traffic raster tile source + layer */
+function addTraffic(map) {
+  if (!map || map.getSource(TRAFFIC_SOURCE)) return
+  const config = getConfig()
+  const tr = config?.traffic
+  if (!tr?.proxy_url) return
+
+  const tileUrl = tr.proxy_url.replace('{z}', '{z}').replace('{x}', '{x}').replace('{y}', '{y}')
+
+  map.addSource(TRAFFIC_SOURCE, {
+    type: 'raster',
+    tiles: [tileUrl],
+    tileSize: 256,
+    maxzoom: 18,
+  })
+
+  map.addLayer({
+    id: TRAFFIC_LAYER,
+    type: 'raster',
+    source: TRAFFIC_SOURCE,
+    paint: {
+      'raster-opacity': 0.6,
+    },
+  })
+}
+
+/** Remove traffic layer + source */
+function removeTraffic(map) {
+  if (!map) return
+  if (map.getLayer(TRAFFIC_LAYER)) map.removeLayer(TRAFFIC_LAYER)
+  if (map.getSource(TRAFFIC_SOURCE)) map.removeSource(TRAFFIC_SOURCE)
+}
+
 const MapView = forwardRef(function MapView(_, ref) {
   const mapRef = useRef(null)
   const mapInstance = useRef(null)
@@ -46,6 +127,8 @@ const MapView = forwardRef(function MapView(_, ref) {
   const previewMarkerRef = useRef(null)
   const watchIdRef = useRef(null)
   const currentThemeRef = useRef('dark')
+  // Track which overlay layers are currently active (for theme swap re-add)
+  const activeLayersRef = useRef({ hillshade: false, traffic: false })
   // Flag to suppress map-click when a stop pin was clicked
   const pinClickedRef = useRef(false)
 
@@ -65,6 +148,30 @@ const MapView = forwardRef(function MapView(_, ref) {
     getMap() {
       return mapInstance.current
     },
+    addHillshadeLayer() {
+      const map = mapInstance.current
+      if (!map) return
+      addHillshade(map)
+      activeLayersRef.current.hillshade = true
+    },
+    removeHillshadeLayer() {
+      const map = mapInstance.current
+      if (!map) return
+      removeHillshade(map)
+      activeLayersRef.current.hillshade = false
+    },
+    addTrafficLayer() {
+      const map = mapInstance.current
+      if (!map) return
+      addTraffic(map)
+      activeLayersRef.current.traffic = true
+    },
+    removeTrafficLayer() {
+      const map = mapInstance.current
+      if (!map) return
+      removeTraffic(map)
+      activeLayersRef.current.traffic = false
+    },
   }))
 
   // Initialize map
@@ -164,6 +271,26 @@ const MapView = forwardRef(function MapView(_, ref) {
         type: 'geojson',
         data: { type: 'FeatureCollection', features: [] },
       })
+
+      // Restore overlay layers from localStorage prefs
+      try {
+        const raw = localStorage.getItem('navi-layer-prefs')
+        if (raw) {
+          const prefs = JSON.parse(raw)
+          if (prefs.hillshade && hasFeature('has_hillshade')) {
+            addHillshade(map)
+            activeLayersRef.current.hillshade = true
+          }
+          if (prefs.traffic && hasFeature('has_traffic_overlay')) {
+            addTraffic(map)
+            activeLayersRef.current.traffic = true
+          }
+        } else if (hasFeature('has_hillshade')) {
+          // Default: hillshade ON if available
+          addHillshade(map)
+          activeLayersRef.current.hillshade = true
+        }
+      } catch {}
     })
 
     mapInstance.current = map
@@ -221,12 +348,17 @@ const MapView = forwardRef(function MapView(_, ref) {
 
     map.setStyle(buildStyle(theme), { diff: false })
 
-    // Re-add route source after style swap
+    // Re-add sources/layers after style swap
     map.once('style.load', () => {
       map.addSource(ROUTE_SOURCE, {
         type: 'geojson',
         data: { type: 'FeatureCollection', features: [] },
       })
+
+      // Re-add active overlay layers
+      if (activeLayersRef.current.hillshade) addHillshade(map)
+      if (activeLayersRef.current.traffic) addTraffic(map)
+
       // Restore view
       map.jumpTo({ center, zoom, bearing, pitch })
       // Re-render route if exists
diff --git a/src/index.css b/src/index.css
index 671ac29..ee35cf0 100644
--- a/src/index.css
+++ b/src/index.css
@@ -282,3 +282,103 @@ body {
   transform: translateX(0);
   opacity: 1;
 }
+
+/* ═══ LAYER CONTROL ═══ */
+.layer-control {
+  position: absolute;
+  bottom: 32px;
+  right: 10px;
+  z-index: 10;
+}
+
+.layer-control-btn {
+  width: 36px;
+  height: 36px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background: var(--bg-raised);
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  color: var(--text-secondary);
+  cursor: pointer;
+  box-shadow: var(--shadow);
+  transition: color 0.1s, border-color 0.1s;
+}
+
+.layer-control-btn:hover {
+  color: var(--text-primary);
+  border-color: var(--accent);
+}
+
+.layer-control-popover {
+  position: absolute;
+  bottom: 44px;
+  right: 0;
+  min-width: 160px;
+  background: var(--bg-raised);
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  padding: 8px 0;
+  box-shadow: var(--shadow-lg);
+}
+
+.layer-control-header {
+  padding: 4px 12px 6px;
+  font-size: var(--text-xs);
+  font-weight: 600;
+  color: var(--text-tertiary);
+  text-transform: uppercase;
+  letter-spacing: 0.05em;
+}
+
+.layer-control-item {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 6px 12px;
+  cursor: pointer;
+  transition: background 0.1s;
+}
+
+.layer-control-item:hover {
+  background: var(--bg-overlay);
+}
+
+.layer-control-label {
+  font-size: var(--text-sm);
+  color: var(--text-primary);
+}
+
+.layer-control-toggle {
+  appearance: none;
+  width: 32px;
+  height: 18px;
+  background: var(--border);
+  border-radius: 9px;
+  position: relative;
+  cursor: pointer;
+  transition: background 0.15s;
+  flex-shrink: 0;
+  margin-left: 12px;
+}
+
+.layer-control-toggle::after {
+  content: '';
+  position: absolute;
+  top: 2px;
+  left: 2px;
+  width: 14px;
+  height: 14px;
+  background: var(--text-primary);
+  border-radius: 50%;
+  transition: transform 0.15s;
+}
+
+.layer-control-toggle:checked {
+  background: var(--accent);
+}
+
+.layer-control-toggle:checked::after {
+  transform: translateX(14px);
+}