diff --git a/src/main.cpp b/src/main.cpp
index 6a679fcad..f7f5ff126 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -33,8 +33,6 @@ unsigned int nTransactionsUpdated = 0;
 
 map<uint256, CBlockIndex*> mapBlockIndex;
 CChain chainActive;
-CBlockIndex *pindexBestInvalid;
-set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexValid; // may contain all CBlockIndex*'s that have validness >=BLOCK_VALID_TRANSACTIONS, and must contain those who aren't failed
 int64 nTimeBestReceived = 0;
 int nScriptCheckThreads = 0;
 bool fImporting = false;
@@ -65,7 +63,28 @@ const string strMessageMagic = "Bitcoin Signed Message:\n";
 // Settings
 int64 nTransactionFee = 0;
 
+// Internal stuff
+namespace {
+struct CBlockIndexWorkComparator
+{
+    bool operator()(CBlockIndex *pa, CBlockIndex *pb) {
+        if (pa->nChainWork > pb->nChainWork) return false;
+        if (pa->nChainWork < pb->nChainWork) return true;
 
+        if (pa->GetBlockHash() < pb->GetBlockHash()) return false;
+        if (pa->GetBlockHash() > pb->GetBlockHash()) return true;
+
+        return false; // identical blocks
+    }
+};
+
+CBlockIndex *pindexBestInvalid;
+set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexValid; // may contain all CBlockIndex*'s that have validness >=BLOCK_VALID_TRANSACTIONS, and must contain those who aren't failed
+
+CCriticalSection cs_LastBlockFile;
+CBlockFileInfo infoLastBlockFile;
+int nLastBlockFile = 0;
+}
 
 //////////////////////////////////////////////////////////////////////////////
 //
@@ -2694,10 +2713,6 @@ bool CheckDiskSpace(uint64 nAdditionalBytes)
     return true;
 }
 
-CCriticalSection cs_LastBlockFile;
-CBlockFileInfo infoLastBlockFile;
-int nLastBlockFile = 0;
-
 FILE* OpenDiskFile(const CDiskBlockPos &pos, const char *prefix, bool fReadOnly)
 {
     if (pos.IsNull())
diff --git a/src/main.h b/src/main.h
index 77e479269..d568d8e6b 100644
--- a/src/main.h
+++ b/src/main.h
@@ -26,8 +26,6 @@ class CAddress;
 class CInv;
 class CNode;
 
-struct CBlockIndexWorkComparator;
-
 /** The maximum allowed size for a serialized block, in bytes (network rule) */
 static const unsigned int MAX_BLOCK_SIZE = 1000000;
 /** The maximum size for mined blocks */
@@ -73,7 +71,6 @@ extern CScript COINBASE_FLAGS;
 
 extern CCriticalSection cs_main;
 extern std::map<uint256, CBlockIndex*> mapBlockIndex;
-extern std::set<CBlockIndex*, CBlockIndexWorkComparator> setBlockIndexValid;
 extern unsigned int nTransactionsUpdated;
 extern uint64 nLastBlockTx;
 extern uint64 nLastBlockSize;
@@ -646,10 +643,6 @@ public:
      }
 };
 
-extern CCriticalSection cs_LastBlockFile;
-extern CBlockFileInfo infoLastBlockFile;
-extern int nLastBlockFile;
-
 enum BlockStatus {
     BLOCK_VALID_UNKNOWN      =    0,
     BLOCK_VALID_HEADER       =    1, // parsed, version ok, hash satisfies claimed PoW, 1 <= vtx count <= max, timestamp not in future
@@ -849,19 +842,6 @@ public:
     }
 };
 
-struct CBlockIndexWorkComparator
-{
-    bool operator()(CBlockIndex *pa, CBlockIndex *pb) {
-        if (pa->nChainWork > pb->nChainWork) return false;
-        if (pa->nChainWork < pb->nChainWork) return true;
-
-        if (pa->GetBlockHash() < pb->GetBlockHash()) return false;
-        if (pa->GetBlockHash() > pb->GetBlockHash()) return true;
-
-        return false; // identical blocks
-    }
-};
-
 
 
 /** Used to marshal pointers into hashes for db storage. */