diff --git a/generator/cities_boundaries_builder.cpp b/generator/cities_boundaries_builder.cpp
index 3e56312c43..4466ba5c2a 100644
--- a/generator/cities_boundaries_builder.cpp
+++ b/generator/cities_boundaries_builder.cpp
@@ -24,8 +24,8 @@
 #include "base/logging.hpp"
 #include "base/string_utils.hpp"
 
-#include <map>
 #include <memory>
+#include <unordered_map>
 #include <utility>
 #include <vector>
 
@@ -39,7 +39,8 @@ namespace generator
 {
 namespace
 {
-bool ParseFeatureIdToTestIdMapping(string const & path, map<uint32_t, vector<uint64_t>> & mapping)
+bool ParseFeatureIdToTestIdMapping(string const & path,
+                                   unordered_map<uint32_t, vector<uint64_t>> & mapping)
 {
   bool success = true;
   feature::ForEachFromDat(path, [&](FeatureType & feature, uint32_t fid) {
@@ -106,7 +107,7 @@ bool BuildCitiesBoundaries(string const & dataPath, BoundariesTable & table,
 bool BuildCitiesBoundaries(string const & dataPath, string const & osmToFeaturePath,
                            OsmIdToBoundariesTable & table)
 {
-  using Mapping = map<uint32_t, vector<base::GeoObjectId>>;
+  using Mapping = unordered_map<uint32_t, vector<base::GeoObjectId>>;
 
   return BuildCitiesBoundaries(dataPath, table, [&]() -> unique_ptr<Mapping> {
     Mapping mapping;
@@ -121,7 +122,7 @@ bool BuildCitiesBoundaries(string const & dataPath, string const & osmToFeatureP
 
 bool BuildCitiesBoundariesForTesting(string const & dataPath, TestIdToBoundariesTable & table)
 {
-  using Mapping = map<uint32_t, vector<uint64_t>>;
+  using Mapping = unordered_map<uint32_t, vector<uint64_t>>;
 
   return BuildCitiesBoundaries(dataPath, table, [&]() -> unique_ptr<Mapping> {
     Mapping mapping;
diff --git a/generator/descriptions_section_builder.hpp b/generator/descriptions_section_builder.hpp
index 15450c9856..b0ffe07fd9 100644
--- a/generator/descriptions_section_builder.hpp
+++ b/generator/descriptions_section_builder.hpp
@@ -21,8 +21,8 @@
 #include <cstddef>
 #include <cstdint>
 #include <functional>
-#include <map>
 #include <string>
+#include <unordered_map>
 #include <utility>
 #include <vector>
 
@@ -46,8 +46,8 @@ public:
 private:
   std::string m_mwmPath;
   std::string m_idToWikidataPath;
-  std::map<uint32_t, std::vector<base::GeoObjectId>> m_featureIdToOsmId;
-  std::map<base::GeoObjectId, std::string> m_osmIdToWikidataId;
+  std::unordered_map<uint32_t, std::vector<base::GeoObjectId>> m_featureIdToOsmId;
+  std::unordered_map<base::GeoObjectId, std::string> m_osmIdToWikidataId;
 };
 
 template <class T>
diff --git a/generator/popular_places_section_builder.cpp b/generator/popular_places_section_builder.cpp
index 73dac9ce1b..3623531b02 100644
--- a/generator/popular_places_section_builder.cpp
+++ b/generator/popular_places_section_builder.cpp
@@ -71,11 +71,9 @@ bool BuildPopularPlacesMwmSection(std::string const & srcFilename, std::string c
 
   LOG(LINFO, ("Build Popular Places section"));
 
-  std::unordered_map<uint32_t, base::GeoObjectId> featureIdToOsmId;
-  ForEachOsmId2FeatureId(osmToFeatureFilename,
-                         [&featureIdToOsmId](base::GeoObjectId const & osmId, uint32_t fId) {
-                           featureIdToOsmId.emplace(fId, osmId);
-                         });
+  std::unordered_map<uint32_t, std::vector<base::GeoObjectId>> featureIdToOsmId;
+  if (!ParseFeatureIdToOsmIdMapping(osmToFeatureFilename, featureIdToOsmId))
+    return false;
 
   PopularPlaces places;
   LoadPopularPlaces(srcFilename, places);
@@ -90,9 +88,9 @@ bool BuildPopularPlacesMwmSection(std::string const & srcFilename, std::string c
     PopularityIndex rank = 0;
     auto const it = featureIdToOsmId.find(featureId);
     // Non-OSM features (coastlines, sponsored objects) are not used.
-    if (it != featureIdToOsmId.cend())
+    if (it != featureIdToOsmId.cend() && it->second.size() != 0)
     {
-      auto const placesIt = places.find(it->second);
+      auto const placesIt = places.find(it->second[0]);
 
       if (placesIt != places.cend())
       {
diff --git a/generator/ugc_section_builder.cpp b/generator/ugc_section_builder.cpp
index 78d039dc8d..af0aad89f9 100644
--- a/generator/ugc_section_builder.cpp
+++ b/generator/ugc_section_builder.cpp
@@ -1,7 +1,7 @@
 #include "generator/ugc_section_builder.hpp"
 
-#include "generator/gen_mwm_info.hpp"
 #include "generator/ugc_translator.hpp"
+#include "generator/utils.hpp"
 
 #include "ugc/binary/index_ugc.hpp"
 #include "ugc/binary/serdes.hpp"
@@ -14,6 +14,7 @@
 
 #include <unordered_map>
 #include <utility>
+#include <vector>
 
 namespace generator
 {
@@ -24,15 +25,10 @@ bool BuildUgcMwmSection(std::string const & srcDbFilename, std::string const & m
 
   LOG(LINFO, ("Build UGC section"));
 
-  gen::OsmID2FeatureID osmIdsToFeatureIds;
-  if (!osmIdsToFeatureIds.ReadFromFile(osmToFeatureFilename))
+  std::unordered_map<uint32_t, std::vector<base::GeoObjectId>> featureToOsmId;
+  if (!ParseFeatureIdToOsmIdMapping(osmToFeatureFilename, featureToOsmId))
     return false;
 
-  std::unordered_map<uint32_t, base::GeoObjectId> featureToOsmId;
-  osmIdsToFeatureIds.ForEach([&featureToOsmId](gen::OsmID2FeatureID::ValueT const & p) {
-    featureToOsmId.emplace(p.second /* feature id */, p.first /* osm id */);
-  });
-
   UGCTranslator translator(srcDbFilename);
 
   std::vector<IndexUGC> content;
@@ -46,11 +42,11 @@ bool BuildUgcMwmSection(std::string const & srcDbFilename, std::string const & m
       return;
 
     auto const it = featureToOsmId.find(featureId);
-    CHECK(it != featureToOsmId.cend(),
+    CHECK(it != featureToOsmId.cend() && it->second.size() != 0,
           ("FeatureID", featureId, "is not found in", osmToFeatureFilename));
 
     ugc::UGC result;
-    if (!translator.TranslateUGC(it->second, result))
+    if (!translator.TranslateUGC(it->second[0], result))
       return;
 
     if (result.IsEmpty())
diff --git a/generator/utils.cpp b/generator/utils.cpp
index 60cb8c28e0..e2bc64ce74 100644
--- a/generator/utils.cpp
+++ b/generator/utils.cpp
@@ -45,8 +45,9 @@ void LoadDataSource(DataSource & dataSource)
   }
 }
 
-bool ParseFeatureIdToOsmIdMapping(std::string const & path,
-                                  std::map<uint32_t, std::vector<base::GeoObjectId>> & mapping)
+bool ParseFeatureIdToOsmIdMapping(
+    std::string const & path,
+    std::unordered_map<uint32_t, std::vector<base::GeoObjectId>> & mapping)
 {
   return ForEachOsmId2FeatureId(path,
                                 [&](base::GeoObjectId const & osmId, uint32_t const featureId) {
diff --git a/generator/utils.hpp b/generator/utils.hpp
index 1311e1b50a..ae0a915e1d 100644
--- a/generator/utils.hpp
+++ b/generator/utils.hpp
@@ -15,8 +15,8 @@
 #include "base/logging.hpp"
 
 #include <cstdint>
-#include <map>
 #include <string>
+#include <unordered_map>
 #include <vector>
 
 namespace generator
@@ -63,6 +63,7 @@ bool ForEachOsmId2FeatureId(std::string const & path, ToDo && toDo)
   return true;
 }
 
-bool ParseFeatureIdToOsmIdMapping(std::string const & path,
-                                  std::map<uint32_t, std::vector<base::GeoObjectId>> & mapping);
+bool ParseFeatureIdToOsmIdMapping(
+    std::string const & path,
+    std::unordered_map<uint32_t, std::vector<base::GeoObjectId>> & mapping);
 }  // namespace generator