diff --git a/css/app.css b/css/app.css
index 8b9e5e6ec..2eccfbe2d 100644
--- a/css/app.css
+++ b/css/app.css
@@ -609,7 +609,7 @@ a:hover .icon.out-link   { background-position: -500px -14px;}
     top:0;
     right:0;
     height:60px;
-    z-index: 1;
+    z-index: 9;
     min-width: 768px;
 }
 
@@ -655,7 +655,7 @@ a:hover .icon.out-link   { background-position: -500px -14px;}
     right: 0;
     top: 0;
     height: 59px;
-    z-index: 3;
+    z-index: 50;
 }
 
 .footer {
@@ -683,7 +683,7 @@ a:hover .icon.out-link   { background-position: -500px -14px;}
     float: left;
     height: 100%;
     overflow: hidden;
-    z-index: 2;
+    z-index: 10;
     background: #f6f6f6;
 }
 
@@ -2104,6 +2104,51 @@ img.wiki-image {
     bottom: 0;
 }
 
+/* Map-In-Map
+------------------------------------------------------- */
+
+.map-in-map {
+    position: absolute;
+    overflow: hidden;
+    top: 60px;
+    width: 200px;
+    height: 150px;
+    z-index: 5;
+    background: #000;
+    border: #aaa 1px solid;
+    box-shadow: 0 0 2em black;
+}
+
+.map-in-map-tiles {
+    transform-origin:0 0;
+    -ms-transform-origin:0 0;
+    -webkit-transform-origin:0 0;
+    -moz-transform-origin:0 0;
+    -o-transform-origin:0 0;
+    -moz-user-select: none;
+    -webkit-user-select: none;
+    -ms-user-select: none;
+    user-select: none;
+}
+
+.map-in-map-svg {
+    position: relative;
+    overflow: hidden;
+    height: 100%;
+    width: 100%;
+}
+
+.map-in-map-bbox {
+    fill: none;
+    stroke: rgba(255, 255, 0, 0.75);
+    stroke-width: 1;
+    shape-rendering: crispEdges;
+}
+
+.map-in-map-bbox.thick {
+    stroke-width: 5;
+}
+
 /* About Section
 ------------------------------------------------------- */
 
@@ -2254,7 +2299,7 @@ img.wiki-image {
     left: 0;
     right: 0;
     margin: auto;
-    z-index: 3;
+    z-index: 50;
 }
 
 .modal .loader {
@@ -2266,7 +2311,7 @@ img.wiki-image {
 }
 
 .shaded {
-    z-index: 2;
+    z-index: 49;
     position: absolute;
     top: 0;
     bottom: 0;
diff --git a/css/map.css b/css/map.css
index b3ec162e5..c3edae105 100644
--- a/css/map.css
+++ b/css/map.css
@@ -1032,6 +1032,7 @@ g.turn circle {
 
 /* Cursors */
 
+.map-in-map,
 #map {
     cursor: auto; /* Opera */
     cursor: url(img/cursor-grab.png) 9 9, auto; /* FF */
diff --git a/index.html b/index.html
index 3e71faba6..fd5e3aeba 100644
--- a/index.html
+++ b/index.html
@@ -89,6 +89,7 @@
         <script src='js/id/ui/account.js'></script>
         <script src='js/id/ui/background.js'></script>
         <script src='js/id/ui/map_data.js'></script>
+        <script src='js/id/ui/map_in_map.js'></script>
         <script src='js/id/ui/modes.js'></script>
         <script src='js/id/ui/contributors.js'></script>
         <script src='js/id/ui/help.js'></script>
diff --git a/js/id/ui.js b/js/id/ui.js
index 35ed98bbe..e61c3160d 100644
--- a/js/id/ui.js
+++ b/js/id/ui.js
@@ -32,6 +32,11 @@ iD.ui = function(context) {
             .attr('id', 'map')
             .call(map);
 
+        content.append('div')
+            .attr('class', 'map-in-map')
+            .style('display', 'none')
+            .call(iD.ui.MapInMap(context));
+
         bar.append('div')
             .attr('class', 'spacer col4');
 
diff --git a/js/id/ui/map_in_map.js b/js/id/ui/map_in_map.js
new file mode 100644
index 000000000..385807854
--- /dev/null
+++ b/js/id/ui/map_in_map.js
@@ -0,0 +1,274 @@
+iD.ui.MapInMap = function(context) {
+    var key = '/';
+
+    function map_in_map(selection) {
+        var backgroundLayer = iD.TileLayer(),
+            overlayLayer = iD.TileLayer(),
+            projection = iD.geo.RawMercator(),
+            zoom = d3.behavior.zoom()
+                .scaleExtent([ztok(0.5), ztok(24)])
+                .on('zoom', zoomPan),
+            transformed = false,
+            panning = false,
+            zDiff = 6,    // by default, minimap renders at (main zoom - 6)
+            tStart, tLast, tCurr, kLast, kCurr, tiles, svg, timeoutId;
+
+        function ztok(z) { return 256 * Math.pow(2, z); }
+        function ktoz(k) { return Math.log(k) / Math.LN2 - 8; }
+
+
+        function startMouse() {
+            context.surface().on('mouseup.map-in-map-outside', endMouse);
+            context.container().on('mouseup.map-in-map-outside', endMouse);
+
+            tStart = tLast = tCurr = projection.translate();
+            panning = true;
+        }
+
+
+        function zoomPan() {
+            var e = d3.event.sourceEvent,
+                t = d3.event.translate,
+                k = d3.event.scale,
+                zMain = ktoz(context.projection.scale() * 2 * Math.PI),
+                zMini = ktoz(k);
+
+            // restrict minimap zoom to < (main zoom - 3)
+            if (zMini > zMain - 3) {
+                zMini = zMain - 3;
+                zoom.scale(kCurr).translate(tCurr);  // restore last good values
+                return;
+            }
+
+            tCurr = t;
+            kCurr = k;
+            zDiff = zMain - zMini;
+
+            var scale = kCurr / kLast,
+                tX = Math.round((tCurr[0] / scale - tLast[0]) * scale),
+                tY = Math.round((tCurr[1] / scale - tLast[1]) * scale);
+
+            iD.util.setTransform(tiles, tX, tY, scale);
+            iD.util.setTransform(svg, 0, 0, scale);
+            transformed = true;
+
+            queueRedraw();
+
+            e.preventDefault();
+            e.stopPropagation();
+        }
+
+
+        function endMouse() {
+            context.surface().on('mouseup.map-in-map-outside', null);
+            context.container().on('mouseup.map-in-map-outside', null);
+
+            updateProjection();
+            panning = false;
+
+            if (tCurr[0] !== tStart[0] && tCurr[1] !== tStart[1]) {
+                var dMini = selection.dimensions(),
+                    cMini = [ dMini[0] / 2, dMini[1] / 2 ];
+
+                context.map().center(projection.invert(cMini));
+            }
+        }
+
+
+        function updateProjection() {
+            var loc = context.map().center(),
+                dMini = selection.dimensions(),
+                cMini = [ dMini[0] / 2, dMini[1] / 2 ],
+                tMain = context.projection.translate(),
+                kMain = context.projection.scale(),
+                zMain = ktoz(kMain * 2 * Math.PI),
+                zMini = Math.max(zMain - zDiff, 0.5),
+                kMini = ztok(zMini);
+
+            projection
+                .translate(tMain)
+                .scale(kMini / (2 * Math.PI));
+
+            var s = projection(loc),
+                mouse = panning ? [ tCurr[0] - tStart[0], tCurr[1] - tStart[1] ] : [0, 0],
+                tMini = [
+                    cMini[0] - s[0] + tMain[0] + mouse[0],
+                    cMini[1] - s[1] + tMain[1] + mouse[1]
+                ];
+
+            projection
+                .translate(tMini)
+                .clipExtent([[0, 0], dMini]);
+
+            zoom
+                .center(cMini)
+                .translate(tMini)
+                .scale(kMini);
+
+            tLast = tCurr = tMini;
+            kLast = kCurr = kMini;
+
+            if (transformed) {
+                iD.util.setTransform(tiles, 0, 0);
+                iD.util.setTransform(svg, 0, 0);
+                transformed = false;
+            }
+        }
+
+
+        function redraw() {
+            if (hidden()) return;
+
+            updateProjection();
+
+            var dMini = selection.dimensions(),
+                zMini = ktoz(projection.scale() * 2 * Math.PI);
+
+            // setup tile container
+            tiles = selection
+                .selectAll('.map-in-map-tiles')
+                .data([0]);
+
+            tiles
+                .enter()
+                .append('div')
+                .attr('class', 'map-in-map-tiles');
+
+
+            // redraw background
+            backgroundLayer
+                .source(context.background().baseLayerSource())
+                .projection(projection)
+                .dimensions(dMini);
+
+            var background = tiles
+                .selectAll('.map-in-map-background')
+                .data([0]);
+
+            background.enter()
+                .append('div')
+                .attr('class', 'map-in-map-background');
+
+            background
+                .call(backgroundLayer);
+
+            // redraw overlay
+            var overlaySources = context.background().overlayLayerSources(),
+                hasOverlay = false;
+
+            for (var i = 0; i < overlaySources.length; i++) {
+                if (overlaySources[i].validZoom(zMini)) {
+                    overlayLayer
+                        .source(overlaySources[i])
+                        .projection(projection)
+                        .dimensions(dMini);
+
+                    hasOverlay = true;
+                    break;
+                }
+            }
+
+            var overlay = tiles
+                .selectAll('.map-in-map-overlay')
+                .data(hasOverlay ? [0] : []);
+
+            overlay.enter()
+                .append('div')
+                .attr('class', 'map-in-map-overlay');
+
+            overlay.exit()
+                .remove();
+
+            if (hasOverlay) {
+                overlay
+                    .call(overlayLayer);
+            }
+
+            // redraw bounding box
+            if (!panning) {
+                var getPath = d3.geo.path().projection(projection),
+                    bbox = { type: 'Polygon', coordinates: [context.map().extent().polygon()] };
+
+                svg = selection.selectAll('.map-in-map-svg')
+                    .data([0]);
+
+                svg.enter()
+                    .append('svg')
+                    .attr('class', 'map-in-map-svg');
+
+                var path = svg.selectAll('.map-in-map-bbox')
+                    .data([bbox]);
+
+                path.enter()
+                    .append('path')
+                    .attr('class', 'map-in-map-bbox');
+
+                path
+                    .attr('d', getPath)
+                    .classed('thick', function(d) { return getPath.area(d) < 30; });
+            }
+        }
+
+
+        function queueRedraw() {
+            clearTimeout(timeoutId);
+            timeoutId = setTimeout(function() { redraw(); }, 300);
+        }
+
+
+        function hidden() {
+            return selection.style('display') === 'none';
+        }
+
+
+        function toggle() {
+            if (d3.event) d3.event.preventDefault();
+
+            if (hidden()) {
+                selection
+                    .style('display', 'block')
+                    .style('opacity', 0)
+                    .transition()
+                    .duration(200)
+                    .style('opacity', 1);
+
+                redraw();
+
+            } else {
+                selection
+                    .style('display', 'block')
+                    .style('opacity', 1)
+                    .transition()
+                    .duration(200)
+                    .style('opacity', 0)
+                    .each('end', function() {
+                        d3.select(this).style('display', 'none');
+                    });
+            }
+        }
+
+
+        selection
+            .on('mousedown.map-in-map', startMouse)
+            .on('mouseup.map-in-map', endMouse);
+
+        selection
+            .call(zoom)
+            .on('dblclick.zoom', null);
+
+        context.map()
+            .on('drawn.map-in-map', function(drawn) {
+                if (drawn.full === true) redraw();
+            });
+
+        redraw();
+
+        var keybinding = d3.keybinding('map-in-map')
+            .on(key, toggle);
+
+        d3.select(document)
+            .call(keybinding);
+    }
+
+    return map_in_map;
+};
diff --git a/test/index.html b/test/index.html
index 4f4f6510c..ae6159606 100644
--- a/test/index.html
+++ b/test/index.html
@@ -84,6 +84,7 @@
     <script src='../js/id/ui/account.js'></script>
     <script src='../js/id/ui/background.js'></script>
     <script src='../js/id/ui/map_data.js'></script>
+    <script src='../js/id/ui/map_in_map.js'></script>
     <script src='../js/id/ui/modes.js'></script>
     <script src='../js/id/ui/contributors.js'></script>
     <script src='../js/id/ui/geolocate.js'></script>