diff --git a/.github/workflows/dendrite.yml b/.github/workflows/dendrite.yml
index 49bf3f6c6..acc1c53e2 100644
--- a/.github/workflows/dendrite.yml
+++ b/.github/workflows/dendrite.yml
@@ -78,7 +78,7 @@ jobs:
 
   # run go test with go 1.19
   test:
-    timeout-minutes: 10
+    timeout-minutes: 15
     name: Unit tests
     runs-on: ubuntu-latest
     # Service containers to run with `container-job`
diff --git a/syncapi/routing/location_sync.go b/syncapi/routing/location_sync.go
new file mode 100644
index 000000000..40ba3f850
--- /dev/null
+++ b/syncapi/routing/location_sync.go
@@ -0,0 +1,64 @@
+// Copyright 2017 Vector Creations Ltd
+//
+// 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 routing
+
+import (
+	"database/sql"
+	"net/http"
+
+	"github.com/matrix-org/dendrite/roomserver/api"
+	"github.com/matrix-org/dendrite/syncapi/storage"
+	"github.com/matrix-org/dendrite/syncapi/types"
+	userapi "github.com/matrix-org/dendrite/userapi/api"
+	"github.com/matrix-org/gomatrixserverlib/spec"
+	"github.com/matrix-org/util"
+	"github.com/sirupsen/logrus"
+)
+
+// https://matrix.org/docs/spec/client_server/r0.6.0#get-matrix-client-r0-rooms-roomid-joined-members
+type getLocationSyncResponse struct {
+	RecentLocations types.MultiRoom `json:"recent_locations"`
+}
+
+// GetLocationSync return each VISIBLE user's most recent location update in the room.
+// This is used for the case of newly joined users which require catching up on location events of users,
+// but aren't able to retrieve certain location events from /sync, since they joined after them.
+func GetLocationSync(
+	req *http.Request, device *userapi.Device, roomID string,
+	syncDB storage.Database, rsAPI api.SyncRoomserverAPI,
+) util.JSONResponse {
+	snapshot, err := syncDB.NewDatabaseSnapshot(req.Context())
+	if err != nil {
+		logrus.WithError(err).Error("Failed to get snapshot for locations sync")
+		return util.JSONResponse{
+			Code: http.StatusInternalServerError,
+			JSON: spec.InternalServerError{},
+		}
+	}
+	mr, err := snapshot.SelectAllMultiRoomDataInRoom(req.Context(), roomID)
+	if err != nil {
+		if err != sql.ErrNoRows {
+			util.GetLogger(req.Context()).WithError(err).Error("failed to select all most recent multiroom data for room")
+			return util.JSONResponse{
+				Code: http.StatusInternalServerError,
+				JSON: spec.InternalServerError{},
+			}
+		}
+	}
+	return util.JSONResponse{
+		Code: http.StatusOK,
+		JSON: getLocationSyncResponse{RecentLocations: mr},
+	}
+}
diff --git a/syncapi/routing/routing.go b/syncapi/routing/routing.go
index 8542c0b73..ab2247773 100644
--- a/syncapi/routing/routing.go
+++ b/syncapi/routing/routing.go
@@ -207,4 +207,14 @@ func Setup(
 			return GetMemberships(req, device, vars["roomID"], syncDB, rsAPI, true, &membership, nil, at)
 		}),
 	).Methods(http.MethodGet, http.MethodOptions)
+
+	v3mux.Handle("/rooms/{roomID}/location_sync",
+		httputil.MakeAuthAPI("location_sync", userAPI, func(req *http.Request, device *userapi.Device) util.JSONResponse {
+			vars, err := httputil.URLDecodeMapValues(mux.Vars(req))
+			if err != nil {
+				return util.ErrorResponse(err)
+			}
+			return GetLocationSync(req, device, vars["roomID"], syncDB, rsAPI)
+		}),
+	).Methods(http.MethodGet, http.MethodOptions)
 }
diff --git a/syncapi/storage/interface.go b/syncapi/storage/interface.go
index 09ce02396..b777792b6 100644
--- a/syncapi/storage/interface.go
+++ b/syncapi/storage/interface.go
@@ -111,6 +111,7 @@ type DatabaseTransaction interface {
 	PresenceAfter(ctx context.Context, after types.StreamPosition, filter synctypes.EventFilter) (map[string]*types.PresenceInternal, error)
 	RelationsFor(ctx context.Context, roomID, eventID, relType, eventType string, from, to types.StreamPosition, backwards bool, limit int) (events []types.StreamEvent, prevBatch, nextBatch string, err error)
 	SelectMultiRoomData(ctx context.Context, r *types.Range, joinedRooms []string) (types.MultiRoom, error)
+	SelectAllMultiRoomDataInRoom(ctx context.Context, roomId string) (types.MultiRoom, error)
 }
 
 type Database interface {
diff --git a/syncapi/storage/postgres/multiroomcast_table.go b/syncapi/storage/postgres/multiroomcast_table.go
index a7672f939..60e4acf85 100644
--- a/syncapi/storage/postgres/multiroomcast_table.go
+++ b/syncapi/storage/postgres/multiroomcast_table.go
@@ -25,8 +25,15 @@ WHERE v.room_id = ANY($1)
 AND id > $2
 AND id <= $3`
 
+const selectAllMultiRoomCastInRoomSQL = `SELECT d.user_id, d.type, d.data, d.ts FROM syncapi_multiroom_data AS d
+JOIN syncapi_multiroom_visibility AS v
+ON d.user_id = v.user_id
+AND concat(d.type, '.visibility') = v.type
+WHERE v.room_id = $1`
+
 type multiRoomStatements struct {
-	selectMultiRoomCast *sql.Stmt
+	selectMultiRoomCast          *sql.Stmt
+	selectAllMultiRoomCastInRoom *sql.Stmt
 }
 
 func NewPostgresMultiRoomCastTable(db *sql.DB) (tables.MultiRoom, error) {
@@ -37,6 +44,7 @@ func NewPostgresMultiRoomCastTable(db *sql.DB) (tables.MultiRoom, error) {
 	}
 	return r, sqlutil.StatementList{
 		{&r.selectMultiRoomCast, selectMultiRoomCastSQL},
+		{&r.selectAllMultiRoomCastInRoom, selectAllMultiRoomCastInRoomSQL},
 	}.Prepare(db)
 }
 
@@ -59,3 +67,23 @@ func (s *multiRoomStatements) SelectMultiRoomData(ctx context.Context, r *types.
 	}
 	return data, rows.Err()
 }
+
+func (s *multiRoomStatements) SelectAllMultiRoomDataInRoom(ctx context.Context, roomId string, txn *sql.Tx) ([]*types.MultiRoomDataRow, error) {
+	rows, err := sqlutil.TxStmt(txn, s.selectAllMultiRoomCastInRoom).QueryContext(ctx, roomId)
+	if err != nil {
+		return nil, err
+	}
+	data := make([]*types.MultiRoomDataRow, 0)
+	defer internal.CloseAndLogIfError(ctx, rows, "SelectAllMultiRoomDataInRoom: rows.close() failed")
+	var t time.Time
+	for rows.Next() {
+		r := types.MultiRoomDataRow{}
+		err = rows.Scan(&r.UserId, &r.Type, &r.Data, &t)
+		r.Timestamp = t.UnixMilli()
+		if err != nil {
+			return nil, fmt.Errorf("rows scan: %w", err)
+		}
+		data = append(data, &r)
+	}
+	return data, rows.Err()
+}
diff --git a/syncapi/storage/shared/storage_sync.go b/syncapi/storage/shared/storage_sync.go
index cd4a8bd6c..7a6189be6 100644
--- a/syncapi/storage/shared/storage_sync.go
+++ b/syncapi/storage/shared/storage_sync.go
@@ -826,3 +826,22 @@ func (d *DatabaseTransaction) SelectMultiRoomData(ctx context.Context, r *types.
 	return mr, nil
 
 }
+
+func (d *DatabaseTransaction) SelectAllMultiRoomDataInRoom(ctx context.Context, roomId string) (types.MultiRoom, error) {
+	rows, err := d.MultiRoom.SelectAllMultiRoomDataInRoom(ctx, roomId, d.txn)
+	if err != nil {
+		return nil, fmt.Errorf("select all multi room data in room: %w", err)
+	}
+	mr := make(types.MultiRoom, 3)
+	for _, row := range rows {
+		if mr[row.UserId] == nil {
+			mr[row.UserId] = make(map[string]types.MultiRoomData)
+		}
+		mr[row.UserId][row.Type] = types.MultiRoomData{
+			Content:        row.Data,
+			OriginServerTs: row.Timestamp,
+		}
+	}
+	return mr, nil
+
+}
diff --git a/syncapi/storage/tables/interface.go b/syncapi/storage/tables/interface.go
index 5085354e4..e082ee7d3 100644
--- a/syncapi/storage/tables/interface.go
+++ b/syncapi/storage/tables/interface.go
@@ -245,4 +245,5 @@ type Relations interface {
 
 type MultiRoom interface {
 	SelectMultiRoomData(ctx context.Context, r *types.Range, joinedRooms []string, txn *sql.Tx) ([]*types.MultiRoomDataRow, error)
+	SelectAllMultiRoomDataInRoom(ctx context.Context, roomId string, txn *sql.Tx) ([]*types.MultiRoomDataRow, error)
 }