diff --git a/simplesvnbrowser/main_window.py b/simplesvnbrowser/main_window.py
index 59e8fab..5e3f8e1 100644
--- a/simplesvnbrowser/main_window.py
+++ b/simplesvnbrowser/main_window.py
@@ -1,3 +1,4 @@
+import re
 import gi
 gi.require_version("Gtk", "3.0")
 from gi.repository import Gtk
@@ -9,6 +10,7 @@ class MainWindow(Gtk.Window):
     def __init__(self, url):
         super().__init__(title = "Simple SVN Browser v%s" % VERSION)
 
+        self.repo_root = None
         self.cache_file = CacheFile()
         if (self.cache_file["width"] is not None and
                 self.cache_file["height"] is not None):
@@ -16,9 +18,11 @@ class MainWindow(Gtk.Window):
                                   self.cache_file["height"])
 
         top_hbox = Gtk.Box()
-        address_entry = Gtk.Entry(text = url)
+        self.address_entry = Gtk.Entry(text = url)
+        self.address_entry.connect("activate", self.on_go_button_clicked)
         go_button = Gtk.Button(label = "Go")
-        top_hbox.pack_start(address_entry, True, True, 0)
+        go_button.connect("clicked", self.on_go_button_clicked)
+        top_hbox.pack_start(self.address_entry, True, True, 0)
         top_hbox.pack_start(go_button, False, True, 0)
 
         vbox = Gtk.Box(orientation = Gtk.Orientation.VERTICAL)
@@ -45,6 +49,10 @@ class MainWindow(Gtk.Window):
     def run(self):
         Gtk.main()
 
+    def on_go_button_clicked(self, widget):
+        self.__refresh(self.address_entry.get_text())
+        return True
+
     def __close(self, *more):
         size = self.get_size()
         position = self.get_position()
@@ -55,3 +63,29 @@ class MainWindow(Gtk.Window):
         self.cache_file.write()
         Gtk.main_quit()
         return True
+
+    def __refresh(self, url):
+        self.__refresh_repo_root(url)
+        if self.repo_root is not None:
+            self.__refresh_contents(url)
+        else:
+            # TODO: invalidate bottom pane
+            pass
+
+    def __refresh_repo_root(self, url):
+        if (self.repo_root is not None and
+                (url == self.repo_root or
+                 url.startswith(self.repo_root + "/"))):
+            # Up to date
+            pass
+        else:
+            stdout, _ = run_svn(["info", url])
+            m = re.search(r'^Repository Root: (.*)$', stdout, re.MULTILINE)
+            if m is not None:
+                self.repo_root = m.group(1)
+            else:
+                self.repo_root = None
+
+    def __refresh_contents(self, url):
+        stdout, _ = run_svn(["ls", url])
+        # TODO: finish