diff --git a/gossipd/gossip_wire.csv b/gossipd/gossip_wire.csv
index d90434291..0e58caf93 100644
--- a/gossipd/gossip_wire.csv
+++ b/gossipd/gossip_wire.csv
@@ -164,3 +164,7 @@ msgdata,gossip_get_incoming_channels,private_too,?bool,
 msgtype,gossip_get_incoming_channels_reply,3125
 msgdata,gossip_get_incoming_channels_reply,num,u16,
 msgdata,gossip_get_incoming_channels_reply,route_info,route_info,num
+
+# master -> gossipd: blockheight increased.
+msgtype,gossip_new_blockheight,3026
+msgdata,gossip_new_blockheight,blockheight,u32,
diff --git a/gossipd/gossipd.c b/gossipd/gossipd.c
index 33d90ac6c..ae16d9978 100644
--- a/gossipd/gossipd.c
+++ b/gossipd/gossipd.c
@@ -2344,6 +2344,15 @@ static struct io_plan *get_incoming_channels(struct io_conn *conn,
 	return daemon_conn_read_next(conn, daemon->master);
 }
 
+static struct io_plan *new_blockheight(struct io_conn *conn,
+				       struct daemon *daemon,
+				       const u8 *msg)
+{
+	if (!fromwire_gossip_new_blockheight(msg, &daemon->current_blockheight))
+		master_badmsg(WIRE_GOSSIP_NEW_BLOCKHEIGHT, msg);
+	return daemon_conn_read_next(conn, daemon->master);
+}
+
 #if DEVELOPER
 static struct io_plan *query_scids_req(struct io_conn *conn,
 				       struct daemon *daemon,
@@ -2801,6 +2810,9 @@ static struct io_plan *recv_req(struct io_conn *conn,
 	case WIRE_GOSSIP_GET_INCOMING_CHANNELS:
 		return get_incoming_channels(conn, daemon, msg);
 
+	case WIRE_GOSSIP_NEW_BLOCKHEIGHT:
+		return new_blockheight(conn, daemon, msg);
+
 #if DEVELOPER
 	case WIRE_GOSSIP_QUERY_SCIDS:
 		return query_scids_req(conn, daemon, msg);
@@ -2875,6 +2887,7 @@ int main(int argc, char *argv[])
 	daemon->unknown_scids = tal_arr(daemon, struct short_channel_id, 0);
 	daemon->gossip_missing = NULL;
 	daemon->node_announce_timer = NULL;
+	daemon->current_blockheight = 0; /* i.e. unknown */
 
 	/* Note the use of time_mono() here.  That's a monotonic clock, which
 	 * is really useful: it can only be used to measure relative events
diff --git a/gossipd/gossipd.h b/gossipd/gossipd.h
index 09c814cd9..f9d3e2514 100644
--- a/gossipd/gossipd.h
+++ b/gossipd/gossipd.h
@@ -18,6 +18,9 @@ struct daemon {
 	/* Peers we are gossiping to: id is unique */
 	struct list_head peers;
 
+	/* Current blockheight: 0 means we're not up-to-date. */
+	u32 current_blockheight;
+
 	/* Connection to lightningd. */
 	struct daemon_conn *master;
 
diff --git a/gossipd/test/run-crc32_of_update.c b/gossipd/test/run-crc32_of_update.c
index 6b25a5c3a..50ba85211 100644
--- a/gossipd/test/run-crc32_of_update.c
+++ b/gossipd/test/run-crc32_of_update.c
@@ -100,6 +100,9 @@ bool fromwire_gossip_get_txout_reply(const tal_t *ctx UNNEEDED, const void *p UN
 /* Generated stub for fromwire_gossip_local_channel_close */
 bool fromwire_gossip_local_channel_close(const void *p UNNEEDED, struct short_channel_id *short_channel_id UNNEEDED)
 { fprintf(stderr, "fromwire_gossip_local_channel_close called!\n"); abort(); }
+/* Generated stub for fromwire_gossip_new_blockheight */
+bool fromwire_gossip_new_blockheight(const void *p UNNEEDED, u32 *blockheight UNNEEDED)
+{ fprintf(stderr, "fromwire_gossip_new_blockheight called!\n"); abort(); }
 /* Generated stub for fromwire_gossip_new_peer */
 bool fromwire_gossip_new_peer(const void *p UNNEEDED, struct node_id *id UNNEEDED, bool *gossip_queries_feature UNNEEDED, bool *initial_routing_sync UNNEEDED)
 { fprintf(stderr, "fromwire_gossip_new_peer called!\n"); abort(); }
diff --git a/gossipd/test/run-extended-info.c b/gossipd/test/run-extended-info.c
index 1d44f4649..9fc703fee 100644
--- a/gossipd/test/run-extended-info.c
+++ b/gossipd/test/run-extended-info.c
@@ -108,6 +108,9 @@ bool fromwire_gossip_get_txout_reply(const tal_t *ctx UNNEEDED, const void *p UN
 /* Generated stub for fromwire_gossip_local_channel_close */
 bool fromwire_gossip_local_channel_close(const void *p UNNEEDED, struct short_channel_id *short_channel_id UNNEEDED)
 { fprintf(stderr, "fromwire_gossip_local_channel_close called!\n"); abort(); }
+/* Generated stub for fromwire_gossip_new_blockheight */
+bool fromwire_gossip_new_blockheight(const void *p UNNEEDED, u32 *blockheight UNNEEDED)
+{ fprintf(stderr, "fromwire_gossip_new_blockheight called!\n"); abort(); }
 /* Generated stub for fromwire_gossip_new_peer */
 bool fromwire_gossip_new_peer(const void *p UNNEEDED, struct node_id *id UNNEEDED, bool *gossip_queries_feature UNNEEDED, bool *initial_routing_sync UNNEEDED)
 { fprintf(stderr, "fromwire_gossip_new_peer called!\n"); abort(); }
diff --git a/lightningd/gossip_control.c b/lightningd/gossip_control.c
index ea37d1560..34065dcea 100644
--- a/lightningd/gossip_control.c
+++ b/lightningd/gossip_control.c
@@ -152,6 +152,7 @@ static unsigned gossip_msg(struct subd *gossip, const u8 *msg, const int *fds)
 	case WIRE_GOSSIP_DEV_MEMLEAK:
 	case WIRE_GOSSIP_DEV_COMPACT_STORE:
 	case WIRE_GOSSIP_DEV_SET_TIME:
+	case WIRE_GOSSIP_NEW_BLOCKHEIGHT:
 	/* This is a reply, so never gets through to here. */
 	case WIRE_GOSSIP_GETNODES_REPLY:
 	case WIRE_GOSSIP_GETROUTE_REPLY:
@@ -175,6 +176,22 @@ static unsigned gossip_msg(struct subd *gossip, const u8 *msg, const int *fds)
 	return 0;
 }
 
+void gossip_notify_new_block(struct lightningd *ld, u32 blockheight)
+{
+	/* Only notify gossipd once we're synced. */
+	if (!topology_synced(ld->topology))
+		return;
+
+	subd_send_msg(ld->gossip,
+		      take(towire_gossip_new_blockheight(NULL, blockheight)));
+}
+
+static void gossip_topology_synced(struct chain_topology *topo, void *unused)
+{
+	/* Now we start telling gossipd about blocks. */
+	gossip_notify_new_block(topo->ld, get_block_height(topo));
+}
+
 /* Create the `gossipd` subdaemon and send the initialization
  * message */
 void gossip_init(struct lightningd *ld, int connectd_fd)
@@ -190,6 +207,10 @@ void gossip_init(struct lightningd *ld, int connectd_fd)
 	if (!ld->gossip)
 		err(1, "Could not subdaemon gossip");
 
+	/* We haven't started topology yet, so tell us when we're synced. */
+	topology_add_sync_waiter(ld->gossip, ld->topology,
+				 gossip_topology_synced, NULL);
+
 	msg = towire_gossipctl_init(
 	    tmpctx,
 	    &get_chainparams(ld)->genesis_blockhash, &ld->id,
diff --git a/lightningd/gossip_control.h b/lightningd/gossip_control.h
index bc33cbc19..7d6254e29 100644
--- a/lightningd/gossip_control.h
+++ b/lightningd/gossip_control.h
@@ -12,4 +12,6 @@ void gossip_init(struct lightningd *ld, int connectd_fd);
 void gossipd_notify_spend(struct lightningd *ld,
 			  const struct short_channel_id *scid);
 
+void gossip_notify_new_block(struct lightningd *ld, u32 blockheight);
+
 #endif /* LIGHTNING_LIGHTNINGD_GOSSIP_CONTROL_H */
diff --git a/lightningd/lightningd.c b/lightningd/lightningd.c
index 144b95a91..b41420de2 100644
--- a/lightningd/lightningd.c
+++ b/lightningd/lightningd.c
@@ -586,6 +586,7 @@ void notify_new_block(struct lightningd *ld, u32 block_height)
 	/* Inform our subcomponents individually. */
 	htlcs_notify_new_block(ld, block_height);
 	channel_notify_new_block(ld, block_height);
+	gossip_notify_new_block(ld, block_height);
 }
 
 static void on_sigint(int _ UNUSED)
diff --git a/lightningd/test/run-find_my_abspath.c b/lightningd/test/run-find_my_abspath.c
index 4d645e333..948f9fe8a 100644
--- a/lightningd/test/run-find_my_abspath.c
+++ b/lightningd/test/run-find_my_abspath.c
@@ -81,6 +81,9 @@ struct log_book *get_log_book(const struct log *log UNNEEDED)
 /* Generated stub for gossip_init */
 void gossip_init(struct lightningd *ld UNNEEDED, int connectd_fd UNNEEDED)
 { fprintf(stderr, "gossip_init called!\n"); abort(); }
+/* Generated stub for gossip_notify_new_block */
+void gossip_notify_new_block(struct lightningd *ld UNNEEDED, u32 blockheight UNNEEDED)
+{ fprintf(stderr, "gossip_notify_new_block called!\n"); abort(); }
 /* Generated stub for handle_early_opts */
 void handle_early_opts(struct lightningd *ld UNNEEDED, int argc UNNEEDED, char *argv[])
 { fprintf(stderr, "handle_early_opts called!\n"); abort(); }