diff --git a/src/station.cpp b/src/station.cpp
index 737a37de4e..f323dff5a2 100644
--- a/src/station.cpp
+++ b/src/station.cpp
@@ -8,6 +8,7 @@
 /** @file station.cpp Implementation of the station base class. */
 
 #include "stdafx.h"
+#include "core/flatset_type.hpp"
 #include "company_func.h"
 #include "company_base.h"
 #include "roadveh.h"
@@ -425,8 +426,8 @@ void Station::RemoveIndustryToDeliver(Industry *ind)
  */
 void Station::RemoveFromAllNearbyLists()
 {
-	std::set<TownID> towns;
-	std::set<IndustryID> industries;
+	FlatSet<TownID> towns;
+	FlatSet<IndustryID> industries;
 
 	for (const auto &tile : this->catchment_tiles) {
 		TileType type = GetTileType(tile);
diff --git a/src/station_base.h b/src/station_base.h
index 91189baa49..c503118f9e 100644
--- a/src/station_base.h
+++ b/src/station_base.h
@@ -10,6 +10,7 @@
 #ifndef STATION_BASE_H
 #define STATION_BASE_H
 
+#include "core/flatset_type.hpp"
 #include "core/random_func.hpp"
 #include "base_station_base.h"
 #include "newgrf_airport.h"
@@ -627,14 +628,15 @@ void ForAllStationsAroundTiles(const TileArea &ta, Func func)
 	if (Station::GetNumItems() == 0) return;
 
 	/* Not using, or don't have a nearby stations list, so we need to scan. */
-	std::set<StationID> seen_stations;
+	FlatSet<StationID> seen_stations;
 
 	/* Scan an area around the building covering the maximum possible station
 	 * to find the possible nearby stations. */
 	uint max_c = _settings_game.station.modified_catchment ? MAX_CATCHMENT : CA_UNMODIFIED;
 	TileArea ta_ext = TileArea(ta).Expand(max_c);
 	for (TileIndex tile : ta_ext) {
-		if (IsTileType(tile, MP_STATION)) seen_stations.insert(GetStationIndex(tile));
+		if (!IsTileType(tile, MP_STATION)) continue;
+		seen_stations.insert(GetStationIndex(tile));
 	}
 
 	for (StationID stationid : seen_stations) {
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
index 0e93152019..72152ba5d1 100644
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -8,6 +8,7 @@
 /** @file station_cmd.cpp Handling of station tiles. */
 
 #include "stdafx.h"
+#include "core/flatset_type.hpp"
 #include "aircraft.h"
 #include "bridge_map.h"
 #include "vehiclelist_func.h"
@@ -543,7 +544,7 @@ static void ShowRejectOrAcceptNews(const Station *st, CargoTypes cargoes, bool r
 CargoArray GetProductionAroundTiles(TileIndex north_tile, int w, int h, int rad)
 {
 	CargoArray produced{};
-	std::set<IndustryID> industries;
+	FlatSet<IndustryID> industries;
 	TileArea ta = TileArea(north_tile, w, h).Expand(rad);
 
 	/* Loop over all tiles to get the produced cargo of