diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -439,7 +439,7 @@ class localrepository(repo.repository):
     def _readbranchcache(self):
         partial = {}
         try:
-            f = self.opener("branchheads.cache")
+            f = self.opener(os.path.join("cache", "branchheads"))
             lines = f.read().split('\n')
             f.close()
         except (IOError, OSError):
@@ -467,7 +467,8 @@ class localrepository(repo.repository):
 
     def _writebranchcache(self, branches, tip, tiprev):
         try:
-            f = self.opener("branchheads.cache", "w", atomictemp=True)
+            f = self.opener(os.path.join("cache", "branchheads"), "w",
+                            atomictemp=True)
             f.write("%s %s\n" % (hex(tip), tiprev))
             for label, nodes in branches.iteritems():
                 for node in nodes:
diff --git a/mercurial/tags.py b/mercurial/tags.py
--- a/mercurial/tags.py
+++ b/mercurial/tags.py
@@ -12,6 +12,7 @@
 
 from node import nullid, bin, hex, short
 from i18n import _
+import os.path
 import encoding
 import error
 
@@ -151,7 +152,7 @@ def _readtagcache(ui, repo):
     set, caller is responsible for reading tag info from each head.'''
 
     try:
-        cachefile = repo.opener('tags.cache', 'r')
+        cachefile = repo.opener(os.path.join('cache', 'tags'), 'r')
         # force reading the file for static-http
         cachelines = iter(cachefile)
     except IOError:
@@ -185,8 +186,8 @@ def _readtagcache(ui, repo):
                     fnode = bin(line[2])
                     cachefnode[headnode] = fnode
         except (ValueError, TypeError):
-            # corruption of tags.cache, just recompute it
-            ui.warn(_('.hg/tags.cache is corrupt, rebuilding it\n'))
+            # corruption of the tags cache, just recompute it
+            ui.warn(_('.hg/cache/tags is corrupt, rebuilding it\n'))
             cacheheads = []
             cacherevs = []
             cachefnode = {}
@@ -248,7 +249,8 @@ def _readtagcache(ui, repo):
 def _writetagcache(ui, repo, heads, tagfnode, cachetags):
 
     try:
-        cachefile = repo.opener('tags.cache', 'w', atomictemp=True)
+        cachefile = repo.opener(os.path.join('cache', 'tags'), 'w',
+                                atomictemp=True)
     except (OSError, IOError):
         return
 
diff --git a/tests/test-hardlinks.t b/tests/test-hardlinks.t
--- a/tests/test-hardlinks.t
+++ b/tests/test-hardlinks.t
@@ -182,7 +182,8 @@ r4 has hardlinks in the working dir (not
   $ nlinksdir r4
   2 r4/.hg/00changelog.i
   2 r4/.hg/branch
-  2 r4/.hg/branchheads.cache
+  2 r4/.hg/cache/branchheads
+  2 r4/.hg/cache/tags
   2 r4/.hg/dirstate
   2 r4/.hg/hgrc
   2 r4/.hg/last-message.txt
@@ -194,7 +195,6 @@ r4 has hardlinks in the working dir (not
   2 r4/.hg/store/data/f1.i
   2 r4/.hg/store/fncache
   2 r4/.hg/store/undo
-  2 r4/.hg/tags.cache
   2 r4/.hg/undo.branch
   2 r4/.hg/undo.desc
   2 r4/.hg/undo.dirstate
@@ -210,7 +210,8 @@ Update back to revision 11 in r4 should 
   $ nlinksdir r4
   2 r4/.hg/00changelog.i
   1 r4/.hg/branch
-  2 r4/.hg/branchheads.cache
+  2 r4/.hg/cache/branchheads
+  2 r4/.hg/cache/tags
   1 r4/.hg/dirstate
   2 r4/.hg/hgrc
   2 r4/.hg/last-message.txt
@@ -222,7 +223,6 @@ Update back to revision 11 in r4 should 
   2 r4/.hg/store/data/f1.i
   2 r4/.hg/store/fncache
   2 r4/.hg/store/undo
-  2 r4/.hg/tags.cache
   2 r4/.hg/undo.branch
   2 r4/.hg/undo.desc
   2 r4/.hg/undo.dirstate
diff --git a/tests/test-inherit-mode.t b/tests/test-inherit-mode.t
--- a/tests/test-inherit-mode.t
+++ b/tests/test-inherit-mode.t
@@ -105,7 +105,8 @@ group can still write everything
   $ python ../printmodes.py ../push
   00770 ../push/.hg/
   00660 ../push/.hg/00changelog.i
-  00660 ../push/.hg/branchheads.cache
+  00770 ../push/.hg/cache/
+  00660 ../push/.hg/cache/branchheads
   00660 ../push/.hg/requires
   00770 ../push/.hg/store/
   00660 ../push/.hg/store/00changelog.i
diff --git a/tests/test-mq-caches.t b/tests/test-mq-caches.t
--- a/tests/test-mq-caches.t
+++ b/tests/test-mq-caches.t
@@ -1,4 +1,4 @@
-  $ branches=.hg/branchheads.cache
+  $ branches=.hg/cache/branchheads
   $ echo '[extensions]' >> $HGRCPATH
   $ echo 'mq =' >> $HGRCPATH
 
diff --git a/tests/test-mq.t b/tests/test-mq.t
--- a/tests/test-mq.t
+++ b/tests/test-mq.t
@@ -284,12 +284,12 @@ qpop
 qpush with dump of tag cache
 Dump the tag cache to ensure that it has exactly one head after qpush.
 
-  $ rm -f .hg/tags.cache
+  $ rm -f .hg/cache/tags
   $ hg tags > /dev/null
 
-.hg/tags.cache (pre qpush):
+.hg/cache/tags (pre qpush):
 
-  $ cat .hg/tags.cache
+  $ cat .hg/cache/tags
   1 [\da-f]{40} (re)
   
   $ hg qpush
@@ -297,9 +297,9 @@ Dump the tag cache to ensure that it has
   now at: test.patch
   $ hg tags > /dev/null
 
-.hg/tags.cache (post qpush):
+.hg/cache/tags (post qpush):
 
-  $ cat .hg/tags.cache
+  $ cat .hg/cache/tags
   2 [\da-f]{40} (re)
   
   $ checkundo qpush
diff --git a/tests/test-newbranch.t b/tests/test-newbranch.t
--- a/tests/test-newbranch.t
+++ b/tests/test-newbranch.t
@@ -1,4 +1,4 @@
-  $ branchcache=.hg/branchheads.cache
+  $ branchcache=.hg/cache/branchheads
 
   $ hg init t
   $ cd t
diff --git a/tests/test-static-http.t b/tests/test-static-http.t
--- a/tests/test-static-http.t
+++ b/tests/test-static-http.t
@@ -64,7 +64,7 @@ one pull
 
 check for HTTP opener failures when cachefile does not exist
 
-  $ rm .hg/*.cache
+  $ rm .hg/cache/*
   $ cd ../local
   $ echo '[hooks]' >> .hg/hgrc
   $ echo 'changegroup = python ../printenv.py changegroup' >> .hg/hgrc
diff --git a/tests/test-tags.t b/tests/test-tags.t
--- a/tests/test-tags.t
+++ b/tests/test-tags.t
@@ -1,7 +1,7 @@
 Helper functions:
 
   $ cacheexists() {
-  >   [ -f .hg/tags.cache ] && echo "tag cache exists" || echo "no tag cache"
+  >   [ -f .hg/cache/tags ] && echo "tag cache exists" || echo "no tag cache"
   > }
 
   $ dumptags() {
@@ -36,9 +36,9 @@ Setup:
 
 Try corrupting the cache
 
-  $ printf 'a b' > .hg/tags.cache
+  $ printf 'a b' > .hg/cache/tags
   $ hg identify
-  .hg/tags.cache is corrupt, rebuilding it
+  .hg/cache/tags is corrupt, rebuilding it
   acb14030fe0a tip
   $ cacheexists
   tag cache exists
@@ -69,13 +69,13 @@ Create a tag behind hg's back:
 
 Repeat with cold tag cache:
 
-  $ rm -f .hg/tags.cache
+  $ rm -f .hg/cache/tags
   $ hg identify
   b9154636be93 tip
 
 And again, but now unable to write tag cache:
 
-  $ rm -f .hg/tags.cache
+  $ rm -f .hg/cache/tags
   $ chmod 555 .hg
   $ hg identify
   b9154636be93 tip
@@ -216,7 +216,7 @@ Detailed dump of tag info:
 
 Dump cache:
 
-  $ cat .hg/tags.cache
+  $ cat .hg/cache/tags
   4 0c192d7d5e6b78a714de54a2e9627952a877e25a 0c04f2a8af31de17fab7422878ee5a2dadbc943d
   3 6fa450212aeb2a21ed616a54aea39a4a27894cd7 7d3b718c964ef37b89e550ebdafd5789e76ce1b0
   2 7a94127795a33c10a370c93f731fd9fea0b79af6 0c04f2a8af31de17fab7422878ee5a2dadbc943d
@@ -325,7 +325,7 @@ Strip 2: destroy whole branch, no old he
   $ hg tags                  # partly stale
   tip                                4:735c3ca72986
   bar                                0:bbd179dfa0a7
-  $ rm -f .hg/tags.cache
+  $ rm -f .hg/cache/tags
   $ hg tags                  # cold cache
   tip                                4:735c3ca72986
   bar                                0:bbd179dfa0a7