diff --git a/js/control/TrackAnalysis.js b/js/control/TrackAnalysis.js
index 2f230c9..f77aeb5 100644
--- a/js/control/TrackAnalysis.js
+++ b/js/control/TrackAnalysis.js
@@ -142,7 +142,8 @@ BR.TrackAnalysis = L.Class.extend({
                 var wayTags = segments[segmentIndex].feature.properties.messages[messageIndex][9].split(' ');
                 for (var wayTagIndex = 0; wayTagIndex < wayTags.length; wayTagIndex++) {
                     var wayTagParts = wayTags[wayTagIndex].split('=');
-                    switch (wayTagParts[0]) {
+                    var tagName = this.normalizeTagName(wayTagParts[0]);
+                    switch (tagName) {
                         case 'highway':
                             var highwayType = wayTagParts[1];
                             var trackType = '';
@@ -167,10 +168,10 @@ BR.TrackAnalysis = L.Class.extend({
                             break;
                         case 'surface':
                         case 'smoothness':
-                            if (typeof analysis[wayTagParts[0]][wayTagParts[1]] === 'undefined') {
-                                analysis[wayTagParts[0]][wayTagParts[1]] = {
+                            if (typeof analysis[tagName][wayTagParts[1]] === 'undefined') {
+                                analysis[tagName][wayTagParts[1]] = {
                                     formatted_name: i18next.t(
-                                        'sidebar.analysis.data.' + wayTagParts[0] + '.' + wayTagParts[1],
+                                        'sidebar.analysis.data.' + tagName + '.' + wayTagParts[1],
                                         wayTagParts[1]
                                     ),
                                     name: wayTagParts[1],
@@ -178,7 +179,7 @@ BR.TrackAnalysis = L.Class.extend({
                                     distance: 0.0,
                                 };
                             }
-                            analysis[wayTagParts[0]][wayTagParts[1]].distance += parseFloat(
+                            analysis[tagName][wayTagParts[1]].distance += parseFloat(
                                 segments[segmentIndex].feature.properties.messages[messageIndex][3]
                             );
                             break;
@@ -190,6 +191,31 @@ BR.TrackAnalysis = L.Class.extend({
         return this.sortAnalysisData(analysis);
     },
 
+    /**
+     * Normalize the tag name.
+     *
+     * Motivation: The `surface` tag comes in different variations,
+     * e.g. `surface`, `cycleway:surface` etc. We're only interested
+     * in the main tag so all other variations are normalized.
+     *
+     * @param {string} tagName
+     * @returns {string}
+     */
+    normalizeTagName: function (tagName) {
+        // we assume that a tag belongs to the category `surface`,
+        // if that string is contained anywhere in the tag name:
+        if (tagName.indexOf('surface') !== -1) {
+            return 'surface';
+        }
+
+        // the same applies to `smoothness`
+        if (tagName.indexOf('smoothness') !== -1) {
+            return 'smoothness';
+        }
+
+        return tagName;
+    },
+
     /**
      * Transform analysis data for each type into an array, sort it
      * by distance descending and convert it back to an object.
@@ -474,22 +500,31 @@ BR.TrackAnalysis = L.Class.extend({
 
                 return parsed.highway === dataName;
             case 'surface':
-                if (dataName === 'internal-unknown' && typeof parsed.surface !== 'string') {
-                    return true;
-                }
-
-                return typeof parsed.surface === 'string' && parsed.surface === dataName;
+                return this.singleWayTagMatchesData('surface', parsed, dataName);
             case 'smoothness':
-                if (dataName === 'internal-unknown' && typeof parsed.smoothness !== 'string') {
-                    return true;
-                }
-
-                return typeof parsed.smoothness === 'string' && parsed.smoothness === dataName;
+                return this.singleWayTagMatchesData('smoothness', parsed, dataName);
         }
 
         return false;
     },
 
+    singleWayTagMatchesData: function (category, parsedData, lookupValue) {
+        var foundValue = null;
+
+        for (var iterationKey in parsedData) {
+            if (iterationKey.indexOf(category) !== -1) {
+                foundValue = parsedData[iterationKey];
+                break;
+            }
+        }
+
+        if (lookupValue === 'internal-unknown' && foundValue === null) {
+            return true;
+        }
+
+        return foundValue === lookupValue;
+    },
+
     /**
      * Transform a way tags string into an object, for example:
      *