diff --git a/leaflet-osm.js b/leaflet-osm.js
index 6a8fcde..840b1a4 100644
--- a/leaflet-osm.js
+++ b/leaflet-osm.js
@@ -147,9 +147,25 @@ L.OSM.DataLayer = L.FeatureGroup.extend({
       ways = L.OSM.getWays(xml, nodes),
       relations = L.OSM.getRelations(xml, nodes, ways);
 
+    var wayNodes = {}
+    for (var i = 0; i < ways.length; i++) {
+      var way = ways[i];
+      for (var j = 0; j < way.nodes.length; j++) {
+        wayNodes[way.nodes[j].id] = true
+      }
+    }
+
+    var relationNodes = {}
+    for (var i = 0; i < relations.length; i++){
+      var relation = relations[i];
+      for (var j = 0; j < relation.members.length; j++) {
+        relationNodes[relation.members[j].id] = true
+      }
+    }
+
     for (var node_id in nodes) {
       var node = nodes[node_id];
-      if (this.interestingNode(node, ways, relations)) {
+      if (this.interestingNode(node, wayNodes, relationNodes)) {
         features.push(node);
       }
     }
@@ -176,23 +192,9 @@ L.OSM.DataLayer = L.FeatureGroup.extend({
     return false;
   },
 
-  interestingNode: function (node, ways, relations) {
-    var used = false;
-
-    for (var i = 0; i < ways.length; i++) {
-      if (ways[i].nodes.indexOf(node) >= 0) {
-        used = true;
-        break;
-      }
-    }
-
-    if (!used) {
-      return true;
-    }
-
-    for (var i = 0; i < relations.length; i++) {
-      if (relations[i].members.indexOf(node) >= 0)
-        return true;
+  interestingNode: function (node, wayNodes, relationNodes) {
+    if (!wayNodes[node.id] || relationNodes[node.id]) {
+      return true
     }
 
     for (var key in node.tags) {
@@ -309,7 +311,7 @@ L.Util.extend(L.OSM, {
         else // relation-way and relation-relation membership not implemented
           rel_object.members[j] = null;
       }
-
+      rel_object.members = rel_object.members.filter(i => i !== null && i !== undefined)
       result.push(rel_object);
     }
 
diff --git a/test/osm_test.js b/test/osm_test.js
index 3e40767..7807ba1 100644
--- a/test/osm_test.js
+++ b/test/osm_test.js
@@ -146,54 +146,54 @@ describe("L.OSM.DataLayer", function () {
     it("can be added to the map", function () {
       (new L.OSM.DataLayer(null, {asynchronous: true})).addTo(this.map);
     });
-  
+
     it("creates a Polyline for a way", async function () {
       var osm = new L.OSM.DataLayer(fixture("way"), {asynchronous: true});
       await sleep(1);
       layers(osm).length.should.eq(21);
       layers(osm)[20].should.be.an.instanceof(L.Polyline);
     });
-  
+
     it("creates a Polygon for an area", async function () {
       var osm = new L.OSM.DataLayer(fixture("area"), {asynchronous: true});
       await sleep(1);
       layers(osm).length.should.eq(15);
       layers(osm)[14].should.be.an.instanceof(L.Polygon);
     });
-  
+
     it("creates a CircleMarker for an interesting node", async function () {
       var osm = new L.OSM.DataLayer(fixture("node"), {asynchronous: true});
       await sleep(1);
       layers(osm).length.should.eq(1);
       layers(osm)[0].should.be.an.instanceof(L.CircleMarker);
     });
-  
+
     it("creates a Rectangle for a changeset", async function () {
       var osm = new L.OSM.DataLayer(fixture("changeset"), {asynchronous: true});
       await sleep(1);
       layers(osm).length.should.eq(1);
       layers(osm)[0].should.be.an.instanceof(L.Rectangle);
     });
-  
+
     it("sets the feature property on a layer", async function () {
       var osm = new L.OSM.DataLayer(fixture("node"), {asynchronous: true});
       await sleep(1);
       layers(osm)[0].feature.should.have.property("type", "node");
       layers(osm)[0].feature.should.have.property("id", "356552551");
     });
-  
+
     it("sets a way's style", async function () {
       var osm = new L.OSM.DataLayer(fixture("way"), {styles: {way: {color: "red"}}, asynchronous: true});
       await sleep(1);
       layers(osm)[20].options.should.have.property("color", "red");
     });
-  
+
     it("sets an area's style", async function () {
       var osm = new L.OSM.DataLayer(fixture("area"), {styles: {area: {color: "green"}}, asynchronous: true});
       await sleep(1);
       layers(osm)[14].options.should.have.property("color", "green");
     });
-  
+
     it("sets a node's style", async function () {
       var osm = new L.OSM.DataLayer(fixture("node"), {styles: {node: {color: "blue"}}, asynchronous: true});
       await sleep(1);
@@ -219,22 +219,22 @@ describe("L.OSM.DataLayer", function () {
     var layer = new L.OSM.DataLayer();
 
     it("returns true when the node is not in any ways", function () {
-      layer.interestingNode({}, [], []).should.be.true;
+      layer.interestingNode({id: 1}, {}, {}).should.be.true;
     });
 
     it("returns true when the node has an interesting tag", function () {
-      var node = {tags: {interesting: true}};
-      layer.interestingNode(node, [{nodes: [node]}], []).should.be.true;
+      var node = {id: 1, tags: {interesting: true}};
+      layer.interestingNode(node, {1: true}, {1: true}).should.be.true;
     });
 
     it("returns false when the node is used in a way and has uninteresting tags", function () {
-      var node = {tags: {source: 'who cares?'}};
-      layer.interestingNode(node, [{nodes: [node]}], []).should.be.false;
+      var node = {id: 1, tags: {source: 'who cares?'}};
+      layer.interestingNode(node, {1: true}, {}).should.be.false;
     });
 
     it("returns true when the node is used in a way and is used in a relation", function () {
-      var node = {};
-      layer.interestingNode(node, [{nodes: [node]}], [{members: [node]}]).should.be.true;
+      var node = {id: 1};
+      layer.interestingNode(node, {1: true}, {1: true}).should.be.true;
     });
   });
 });