diff --git a/gitiles-servlet/src/main/java/com/google/gitiles/GitilesFilter.java b/gitiles-servlet/src/main/java/com/google/gitiles/GitilesFilter.java
index 57f9306..a69835c 100644
--- a/gitiles-servlet/src/main/java/com/google/gitiles/GitilesFilter.java
+++ b/gitiles-servlet/src/main/java/com/google/gitiles/GitilesFilter.java
@@ -235,7 +235,7 @@
       case REVISION:
         return new RevisionServlet(renderer, linkifier());
       case PATH:
-        return new PathServlet(renderer);
+        return new PathServlet(renderer, urls);
       case DIFF:
         return new DiffServlet(renderer, linkifier());
       case LOG:
diff --git a/gitiles-servlet/src/main/java/com/google/gitiles/GitilesView.java b/gitiles-servlet/src/main/java/com/google/gitiles/GitilesView.java
index 67040fe..ca6315e 100644
--- a/gitiles-servlet/src/main/java/com/google/gitiles/GitilesView.java
+++ b/gitiles-servlet/src/main/java/com/google/gitiles/GitilesView.java
@@ -17,7 +17,6 @@
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.gitiles.GitilesUrls.NAME_ESCAPER;
-import static com.google.gitiles.RevisionParser.PATH_SPLITTER;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Charsets;
@@ -559,7 +558,7 @@
         breadcrumbs.add(breadcrumb(".", copyWithPath().setTreePath("")));
       }
       StringBuilder cur = new StringBuilder();
-      List<String> parts = ImmutableList.copyOf(PATH_SPLITTER.omitEmptyStrings().split(path));
+      List<String> parts = ImmutableList.copyOf(Paths.SPLITTER.omitEmptyStrings().split(path));
       checkArgument(hasSingleTree == null
           || (parts.isEmpty() && hasSingleTree.isEmpty())
           || hasSingleTree.size() == parts.size() - 1,
diff --git a/gitiles-servlet/src/main/java/com/google/gitiles/PathServlet.java b/gitiles-servlet/src/main/java/com/google/gitiles/PathServlet.java
index fff423a..e52cdf6 100644
--- a/gitiles-servlet/src/main/java/com/google/gitiles/PathServlet.java
+++ b/gitiles-servlet/src/main/java/com/google/gitiles/PathServlet.java
@@ -14,9 +14,12 @@
 
 package com.google.gitiles;
 
+import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.gitiles.TreeSoyData.resolveTargetUrl;
+
 import static javax.servlet.http.HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
 import static javax.servlet.http.HttpServletResponse.SC_NOT_FOUND;
+
 import static org.eclipse.jgit.lib.Constants.OBJ_BLOB;
 import static org.eclipse.jgit.lib.Constants.OBJ_COMMIT;
 import static org.eclipse.jgit.lib.Constants.OBJ_TREE;
@@ -103,8 +106,11 @@
     }
   }
 
-  public PathServlet(Renderer renderer) {
+  private final GitilesUrls urls;
+
+  public PathServlet(Renderer renderer, GitilesUrls urls) {
     super(renderer);
+    this.urls = checkNotNull(urls, "urls");
   }
 
   @Override
@@ -376,9 +382,18 @@
     SubmoduleWalk sw = SubmoduleWalk.forPath(ServletUtils.getRepository(req), root,
         view.getTreePath());
 
-    String remoteUrl;
+    String modulesUrl;
+    String remoteUrl = null;
     try {
-      remoteUrl = sw.getRemoteUrl();
+      modulesUrl = sw.getModulesUrl();
+      if (modulesUrl != null && (modulesUrl.startsWith("./") || modulesUrl.startsWith("../"))) {
+        String moduleRepo = Paths.simplifyPathUpToRoot(modulesUrl, view.getRepositoryName());
+        if (moduleRepo != null) {
+          modulesUrl = urls.getBaseGitUrl(req) + moduleRepo;
+        }
+      } else {
+        remoteUrl = sw.getRemoteUrl();
+      }
     } catch (ConfigInvalidException e) {
       throw new IOException(e);
     } finally {
@@ -387,22 +402,25 @@
 
     Map<String, Object> data = Maps.newHashMap();
     data.put("sha", ObjectId.toString(tw.getObjectId(0)));
-    data.put("remoteUrl", remoteUrl);
+    data.put("remoteUrl", remoteUrl != null ? remoteUrl : modulesUrl);
 
-      // TODO(dborowitz): Guess when we can put commit SHAs in the URL.
-      String httpUrl = resolveHttpUrl(remoteUrl);
-      if (httpUrl != null) {
-        data.put("httpUrl", httpUrl);
-      }
+    // TODO(dborowitz): Guess when we can put commit SHAs in the URL.
+    String httpUrl = resolveHttpUrl(remoteUrl);
+    if (httpUrl != null) {
+      data.put("httpUrl", httpUrl);
+    }
 
-      // TODO(sop): Allow caching links by SHA-1 when no S cookie is sent.
-      renderHtml(req, res, "gitiles.pathDetail", ImmutableMap.of(
-          "title", view.getTreePath(),
-          "type", FileType.GITLINK.toString(),
-          "data", data));
+    // TODO(sop): Allow caching links by SHA-1 when no S cookie is sent.
+    renderHtml(req, res, "gitiles.pathDetail", ImmutableMap.of(
+        "title", view.getTreePath(),
+        "type", FileType.GITLINK.toString(),
+        "data", data));
   }
 
   private static String resolveHttpUrl(String remoteUrl) {
+    if (remoteUrl == null) {
+      return null;
+    }
     return VERBATIM_SUBMODULE_URL_PATTERN.matcher(remoteUrl).matches() ? remoteUrl : null;
   }
 }
diff --git a/gitiles-servlet/src/main/java/com/google/gitiles/Paths.java b/gitiles-servlet/src/main/java/com/google/gitiles/Paths.java
new file mode 100644
index 0000000..e4e66af
--- /dev/null
+++ b/gitiles-servlet/src/main/java/com/google/gitiles/Paths.java
@@ -0,0 +1,53 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gitiles;
+
+import com.google.common.base.Splitter;
+import com.google.common.base.Strings;
+import com.google.common.io.Files;
+
+import java.util.StringTokenizer;
+
+/** Static utilities for dealing with pathnames. */
+class Paths {
+  static final Splitter SPLITTER = Splitter.on('/');
+
+  static String simplifyPathUpToRoot(String path, String root) {
+    if (path.startsWith("/")) {
+      return null;
+    }
+
+    root = Strings.nullToEmpty(root);
+    // simplifyPath() normalizes "a/../../" to "a", so manually check whether
+    // the path leads above the root.
+    int depth = new StringTokenizer(root, "/").countTokens();
+    for (String part : SPLITTER.split(path)) {
+      if (part.equals("..")) {
+        depth--;
+        if (depth < 0) {
+          return null;
+        }
+      } else if (!part.isEmpty() && !part.equals(".")) {
+        depth++;
+      }
+    }
+
+    String result = Files.simplifyPath(!root.isEmpty() ? root + "/" + path : path);
+    return !result.equals(".") ? result : "";
+  }
+
+  private Paths() {
+  }
+}
diff --git a/gitiles-servlet/src/main/java/com/google/gitiles/RevisionParser.java b/gitiles-servlet/src/main/java/com/google/gitiles/RevisionParser.java
index cabde7c..ffb59ab 100644
--- a/gitiles-servlet/src/main/java/com/google/gitiles/RevisionParser.java
+++ b/gitiles-servlet/src/main/java/com/google/gitiles/RevisionParser.java
@@ -32,7 +32,6 @@
 
 /** Object to parse revisions out of Gitiles paths. */
 class RevisionParser {
-  static final Splitter PATH_SPLITTER = Splitter.on('/');
   private static final Splitter OPERATOR_SPLITTER = Splitter.on(CharMatcher.anyOf("^~"));
 
   static class Result {
@@ -108,7 +107,7 @@
 
       StringBuilder b = new StringBuilder();
       boolean first = true;
-      for (String part : PATH_SPLITTER.split(path)) {
+      for (String part : Paths.SPLITTER.split(path)) {
         if (part.isEmpty()) {
           return null; // No valid revision contains empty segments.
         }
diff --git a/gitiles-servlet/src/main/java/com/google/gitiles/TreeSoyData.java b/gitiles-servlet/src/main/java/com/google/gitiles/TreeSoyData.java
index 66aa207..4893208 100644
--- a/gitiles-servlet/src/main/java/com/google/gitiles/TreeSoyData.java
+++ b/gitiles-servlet/src/main/java/com/google/gitiles/TreeSoyData.java
@@ -14,15 +14,12 @@
 
 package com.google.gitiles;
 
-import static com.google.gitiles.RevisionParser.PATH_SPLITTER;
 import static org.eclipse.jgit.lib.Constants.OBJ_COMMIT;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Charsets;
-import com.google.common.base.Objects;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
-import com.google.common.io.Files;
 import com.google.gitiles.PathServlet.FileType;
 
 import org.eclipse.jgit.errors.MissingObjectException;
@@ -33,7 +30,6 @@
 import java.io.IOException;
 import java.util.List;
 import java.util.Map;
-import java.util.StringTokenizer;
 
 /** Soy data converter for git trees. */
 public class TreeSoyData {
@@ -51,29 +47,13 @@
   static final int MAX_SYMLINK_SIZE = 16 << 10;
 
   static String resolveTargetUrl(GitilesView view, String target) {
-    if (target.startsWith("/")) {
+    String resolved = Paths.simplifyPathUpToRoot(target, view.getTreePath());
+    if (resolved == null) {
       return null;
     }
-
-    // simplifyPath() normalizes "a/../../" to "a", so manually check whether
-    // the path leads above the git root.
-    String path = Objects.firstNonNull(view.getTreePath(), "");
-    int depth = new StringTokenizer(path, "/").countTokens();
-    for (String part : PATH_SPLITTER.split(target)) {
-      if (part.equals("..")) {
-        depth--;
-        if (depth < 0) {
-          return null;
-        }
-      } else if (!part.isEmpty() && !part.equals(".")) {
-        depth++;
-      }
-    }
-
-    path = Files.simplifyPath(view.getTreePath() + "/" + target);
     return GitilesView.path()
         .copyFrom(view)
-        .setTreePath(!path.equals(".") ? path : "")
+        .setTreePath(resolved)
         .toUrl();
   }
 
@@ -130,8 +110,6 @@
         String target = new String(
             rw.getObjectReader().open(tw.getObjectId(0)).getCachedBytes(),
             Charsets.UTF_8);
-        // TODO(dborowitz): Merge Shawn's changes before copying these methods
-        // in.
         entry.put("targetName", getTargetDisplayName(target));
         String targetUrl = resolveTargetUrl(view, target);
         if (targetUrl != null) {
diff --git a/gitiles-servlet/src/main/resources/com/google/gitiles/templates/PathDetail.soy b/gitiles-servlet/src/main/resources/com/google/gitiles/templates/PathDetail.soy
index 33d38a2..d954268 100644
--- a/gitiles-servlet/src/main/resources/com/google/gitiles/templates/PathDetail.soy
+++ b/gitiles-servlet/src/main/resources/com/google/gitiles/templates/PathDetail.soy
@@ -79,6 +79,10 @@
 {template .gitlinkDetail}
 <div class="gitlink-detail">
   {msg desc="Lead-in text for the git link URL"}Submodule link to {$sha} of{/msg}
-  {sp}{if $httpUrl}<a href="{$httpUrl}">{$remoteUrl}</a>{else}{$remoteUrl}{/if}
+  {if $remoteUrl}
+    {sp}{if $httpUrl}<a href="{$httpUrl}">{$remoteUrl}</a>{else}{$remoteUrl}{/if}
+  {else}
+    {sp}{msg desc="Text describing an unknown submodule URL"}a submodule with an unknown URL{/msg}
+  {/if}
 </div>
 {/template}
diff --git a/gitiles-servlet/src/test/java/com/google/gitiles/PathsTest.java b/gitiles-servlet/src/test/java/com/google/gitiles/PathsTest.java
new file mode 100644
index 0000000..e7cd492
--- /dev/null
+++ b/gitiles-servlet/src/test/java/com/google/gitiles/PathsTest.java
@@ -0,0 +1,45 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gitiles;
+
+import static com.google.gitiles.Paths.simplifyPathUpToRoot;
+
+import junit.framework.TestCase;
+
+/** Tests for {@link Paths}. */
+public class PathsTest extends TestCase {
+  public void testSimplifyPathUpToRoot() throws Exception {
+    String root = "a/b/c";
+    assertNull(simplifyPathUpToRoot("/foo", root));
+    assertEquals("a", simplifyPathUpToRoot("../../", root));
+    assertEquals("a", simplifyPathUpToRoot(".././../", root));
+    assertEquals("a", simplifyPathUpToRoot("..//../", root));
+    assertEquals("a/d", simplifyPathUpToRoot("../../d", root));
+    assertEquals("", simplifyPathUpToRoot("../../..", root));
+    assertEquals("a/d/e", simplifyPathUpToRoot("../../d/e", root));
+    assertEquals("a/b", simplifyPathUpToRoot("../d/../e/../", root));
+    assertNull(simplifyPathUpToRoot("../../../../", root));
+    assertNull(simplifyPathUpToRoot("../../a/../../..", root));
+  }
+
+  public void testSimplifyPathUpToNullRoot() throws Exception {
+    assertNull(simplifyPathUpToRoot("/foo", null));
+    assertNull(simplifyPathUpToRoot("../", null));
+    assertNull(simplifyPathUpToRoot("../../", null));
+    assertNull(simplifyPathUpToRoot(".././../", null));
+    assertEquals("a/b", simplifyPathUpToRoot("a/b", null));
+    assertEquals("a/c", simplifyPathUpToRoot("a/b/../c", null));
+  }
+}