diff --git a/backend/alias/alias.go b/backend/alias/alias.go
index df41019dd..b90037fb6 100644
--- a/backend/alias/alias.go
+++ b/backend/alias/alias.go
@@ -2,13 +2,12 @@ package alias
 
 import (
 	"errors"
-	"path"
-	"path/filepath"
 	"strings"
 
 	"github.com/ncw/rclone/fs"
 	"github.com/ncw/rclone/fs/config/configmap"
 	"github.com/ncw/rclone/fs/config/configstruct"
+	"github.com/ncw/rclone/fs/fspath"
 )
 
 // Register with Fs
@@ -47,14 +46,9 @@ func NewFs(name, root string, m configmap.Mapper) (fs.Fs, error) {
 	if strings.HasPrefix(opt.Remote, name+":") {
 		return nil, errors.New("can't point alias remote at itself - check the value of the remote setting")
 	}
-	_, configName, fsPath, err := fs.ParseRemote(opt.Remote)
+	fsInfo, configName, fsPath, config, err := fs.ConfigFs(opt.Remote)
 	if err != nil {
 		return nil, err
 	}
-	if configName == "local" {
-		root = filepath.Join(fsPath, root)
-		return fs.NewFs(root)
-	}
-	root = path.Join(fsPath, filepath.ToSlash(root))
-	return fs.NewFs(configName + ":" + root)
+	return fsInfo.NewFs(configName, fspath.JoinRootPath(fsPath, root), config)
 }
diff --git a/backend/cache/cache.go b/backend/cache/cache.go
index 7ce38d7ea..b613df377 100644
--- a/backend/cache/cache.go
+++ b/backend/cache/cache.go
@@ -24,6 +24,7 @@ import (
 	"github.com/ncw/rclone/fs/config/configmap"
 	"github.com/ncw/rclone/fs/config/configstruct"
 	"github.com/ncw/rclone/fs/config/obscure"
+	"github.com/ncw/rclone/fs/fspath"
 	"github.com/ncw/rclone/fs/hash"
 	"github.com/ncw/rclone/fs/rc"
 	"github.com/ncw/rclone/fs/walk"
@@ -363,7 +364,7 @@ func NewFs(name, rootPath string, m configmap.Mapper) (fs.Fs, error) {
 		return nil, errors.Wrapf(err, "failed to parse remote %q to wrap", opt.Remote)
 	}
 
-	remotePath := path.Join(wPath, rootPath)
+	remotePath := fspath.JoinRootPath(wPath, rootPath)
 	wrappedFs, wrapErr := wInfo.NewFs(wName, remotePath, wConfig)
 	if wrapErr != nil && wrapErr != fs.ErrorIsFile {
 		return nil, errors.Wrapf(wrapErr, "failed to make remote %s:%s to wrap", wName, remotePath)
diff --git a/backend/crypt/crypt.go b/backend/crypt/crypt.go
index 363d153f4..23fe1c9c0 100644
--- a/backend/crypt/crypt.go
+++ b/backend/crypt/crypt.go
@@ -4,7 +4,6 @@ package crypt
 import (
 	"fmt"
 	"io"
-	"path"
 	"strings"
 	"time"
 
@@ -13,6 +12,7 @@ import (
 	"github.com/ncw/rclone/fs/config/configmap"
 	"github.com/ncw/rclone/fs/config/configstruct"
 	"github.com/ncw/rclone/fs/config/obscure"
+	"github.com/ncw/rclone/fs/fspath"
 	"github.com/ncw/rclone/fs/hash"
 	"github.com/pkg/errors"
 )
@@ -143,11 +143,11 @@ func NewFs(name, rpath string, m configmap.Mapper) (fs.Fs, error) {
 		return nil, errors.Wrapf(err, "failed to parse remote %q to wrap", remote)
 	}
 	// Look for a file first
-	remotePath := path.Join(wPath, cipher.EncryptFileName(rpath))
+	remotePath := fspath.JoinRootPath(wPath, cipher.EncryptFileName(rpath))
 	wrappedFs, err := wInfo.NewFs(wName, remotePath, wConfig)
 	// if that didn't produce a file, look for a directory
 	if err != fs.ErrorIsFile {
-		remotePath = path.Join(wPath, cipher.EncryptDirName(rpath))
+		remotePath = fspath.JoinRootPath(wPath, cipher.EncryptDirName(rpath))
 		wrappedFs, err = wInfo.NewFs(wName, remotePath, wConfig)
 	}
 	if err != fs.ErrorIsFile && err != nil {
diff --git a/fs/fspath/path.go b/fs/fspath/path.go
index baa89bbd2..42f3bcd44 100644
--- a/fs/fspath/path.go
+++ b/fs/fspath/path.go
@@ -5,6 +5,7 @@ import (
 	"path"
 	"path/filepath"
 	"regexp"
+	"strings"
 
 	"github.com/ncw/rclone/fs/driveletter"
 )
@@ -48,3 +49,19 @@ func Split(remote string) (parent string, leaf string) {
 	parent, leaf = path.Split(remotePath)
 	return remoteName + parent, leaf
 }
+
+// JoinRootPath joins any number of path elements into a single path, adding a
+// separating slash if necessary. The result is Cleaned; in particular,
+// all empty strings are ignored.
+// If the first non empty element has a leading "//" this is preserved.
+func JoinRootPath(elem ...string) string {
+	for i, e := range elem {
+		if e != "" {
+			if strings.HasPrefix(e, "//") {
+				return "/" + path.Clean(strings.Join(elem[i:], "/"))
+			}
+			return path.Clean(strings.Join(elem[i:], "/"))
+		}
+	}
+	return ""
+}
diff --git a/fs/fspath/path_test.go b/fs/fspath/path_test.go
index d5b41a473..f900d62be 100644
--- a/fs/fspath/path_test.go
+++ b/fs/fspath/path_test.go
@@ -58,3 +58,32 @@ func TestSplit(t *testing.T) {
 		assert.Equal(t, test.remote, gotParent+gotLeaf, fmt.Sprintf("%s: %q + %q != %q", test.remote, gotParent, gotLeaf, test.remote))
 	}
 }
+func TestJoinRootPath(t *testing.T) {
+	for _, test := range []struct {
+		elements []string
+		want     string
+	}{
+		{nil, ""},
+		{[]string{""}, ""},
+		{[]string{"/"}, "/"},
+		{[]string{"/", "/"}, "/"},
+		{[]string{"/", "//"}, "/"},
+		{[]string{"/root", ""}, "/root"},
+		{[]string{"/root", "/"}, "/root"},
+		{[]string{"/root", "//"}, "/root"},
+		{[]string{"/a/b"}, "/a/b"},
+		{[]string{"//", "/"}, "//"},
+		{[]string{"//server", "path"}, "//server/path"},
+		{[]string{"//server/sub", "path"}, "//server/sub/path"},
+		{[]string{"//server", "//path"}, "//server/path"},
+		{[]string{"//server/sub", "//path"}, "//server/sub/path"},
+		{[]string{"", "//", "/"}, "//"},
+		{[]string{"", "//server", "path"}, "//server/path"},
+		{[]string{"", "//server/sub", "path"}, "//server/sub/path"},
+		{[]string{"", "//server", "//path"}, "//server/path"},
+		{[]string{"", "//server/sub", "//path"}, "//server/sub/path"},
+	} {
+		got := JoinRootPath(test.elements...)
+		assert.Equal(t, test.want, got)
+	}
+}