diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -337,6 +337,7 @@
 	randomenv.cpp
 	rcu.cpp
 	rpc/request.cpp
+	blockdb.cpp
 	support/cleanse.cpp
 	support/lockedpool.cpp
 	sync.cpp
diff --git a/src/blockdb.h b/src/blockdb.h
new file mode 100644
--- /dev/null
+++ b/src/blockdb.h
@@ -0,0 +1,42 @@
+// Copyright 2020 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_BLOCKDB_H
+#define BITCOIN_BLOCKDB_H
+
+#include <flatfile.h>
+
+namespace Consensus {
+struct Params;
+}
+
+class CBlock;
+class CBlockIndex;
+
+/** The pre-allocation chunk size for blk?????.dat files (since 0.8) */
+static constexpr unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; // 16 MiB
+/** The pre-allocation chunk size for rev?????.dat files (since 0.8) */
+static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; // 1 MiB
+
+FlatFileSeq BlockFileSeq();
+FlatFileSeq UndoFileSeq();
+FILE *OpenUndoFile(const FlatFilePos &pos, bool fReadOnly = false);
+
+/**
+ * Translation to a filesystem path.
+ */
+fs::path GetBlockPosFilename(const FlatFilePos &pos);
+
+/**
+ * Open a block file (blk?????.dat).
+ */
+FILE *OpenBlockFile(const FlatFilePos &pos, bool fReadOnly = false);
+
+/** Functions for disk access for blocks */
+bool ReadBlockFromDisk(CBlock &block, const FlatFilePos &pos,
+                       const Consensus::Params &params);
+bool ReadBlockFromDisk(CBlock &block, const CBlockIndex *pindex,
+                       const Consensus::Params &params);
+
+#endif // BITCOIN_BLOCKDB_H
diff --git a/src/blockdb.cpp b/src/blockdb.cpp
new file mode 100644
--- /dev/null
+++ b/src/blockdb.cpp
@@ -0,0 +1,80 @@
+#include <blockdb.h>
+
+#include <blockindex.h>
+#include <clientversion.h>
+#include <pow/pow.h>
+#include <primitives/block.h>
+#include <streams.h>
+#include <util/system.h>
+
+extern RecursiveMutex cs_main;
+
+FlatFileSeq BlockFileSeq() {
+    return FlatFileSeq(GetBlocksDir(), "blk", BLOCKFILE_CHUNK_SIZE);
+}
+
+FlatFileSeq UndoFileSeq() {
+    return FlatFileSeq(GetBlocksDir(), "rev", UNDOFILE_CHUNK_SIZE);
+}
+
+FILE *OpenBlockFile(const FlatFilePos &pos, bool fReadOnly) {
+    return BlockFileSeq().Open(pos, fReadOnly);
+}
+
+/** Open an undo file (rev?????.dat) */
+FILE *OpenUndoFile(const FlatFilePos &pos, bool fReadOnly) {
+    return UndoFileSeq().Open(pos, fReadOnly);
+}
+
+fs::path GetBlockPosFilename(const FlatFilePos &pos) {
+    return BlockFileSeq().FileName(pos);
+}
+
+bool ReadBlockFromDisk(CBlock &block, const FlatFilePos &pos,
+                       const Consensus::Params &params) {
+    block.SetNull();
+
+    // Open history file to read
+    CAutoFile filein(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION);
+    if (filein.IsNull()) {
+        return error("ReadBlockFromDisk: OpenBlockFile failed for %s",
+                     pos.ToString());
+    }
+
+    // Read block
+    try {
+        filein >> block;
+    } catch (const std::exception &e) {
+        return error("%s: Deserialize or I/O error - %s at %s", __func__,
+                     e.what(), pos.ToString());
+    }
+
+    // Check the header
+    if (!CheckProofOfWork(block.GetHash(), block.nBits, params)) {
+        return error("ReadBlockFromDisk: Errors in block header at %s",
+                     pos.ToString());
+    }
+
+    return true;
+}
+
+bool ReadBlockFromDisk(CBlock &block, const CBlockIndex *pindex,
+                       const Consensus::Params &params) {
+    FlatFilePos blockPos;
+    {
+        LOCK(cs_main);
+        blockPos = pindex->GetBlockPos();
+    }
+
+    if (!ReadBlockFromDisk(block, blockPos, params)) {
+        return false;
+    }
+
+    if (block.GetHash() != pindex->GetBlockHash()) {
+        return error("ReadBlockFromDisk(CBlock&, CBlockIndex*): GetHash() "
+                     "doesn't match index for %s at %s",
+                     pindex->ToString(), pindex->GetBlockPos().ToString());
+    }
+
+    return true;
+}
diff --git a/src/index/base.cpp b/src/index/base.cpp
--- a/src/index/base.cpp
+++ b/src/index/base.cpp
@@ -2,6 +2,7 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include <blockdb.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <config.h>
diff --git a/src/index/txindex.cpp b/src/index/txindex.cpp
--- a/src/index/txindex.cpp
+++ b/src/index/txindex.cpp
@@ -4,6 +4,7 @@
 
 #include <index/txindex.h>
 
+#include <blockdb.h>
 #include <chain.h>
 #include <shutdown.h>
 #include <ui_interface.h>
diff --git a/src/init.cpp b/src/init.cpp
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -13,6 +13,7 @@
 #include <amount.h>
 #include <avalanche/processor.h>
 #include <banman.h>
+#include <blockdb.h>
 #include <blockfilter.h>
 #include <chain.h>
 #include <chainparams.h>
diff --git a/src/interfaces/chain.cpp b/src/interfaces/chain.cpp
--- a/src/interfaces/chain.cpp
+++ b/src/interfaces/chain.cpp
@@ -4,6 +4,7 @@
 
 #include <interfaces/chain.h>
 
+#include <blockdb.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <interfaces/handler.h>
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -8,6 +8,7 @@
 #include <addrman.h>
 #include <avalanche/processor.h>
 #include <banman.h>
+#include <blockdb.h>
 #include <blockencodings.h>
 #include <blockvalidity.h>
 #include <chain.h>
diff --git a/src/rest.cpp b/src/rest.cpp
--- a/src/rest.cpp
+++ b/src/rest.cpp
@@ -3,6 +3,7 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include <blockdb.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <config.h>
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -6,6 +6,7 @@
 #include <rpc/blockchain.h>
 
 #include <amount.h>
+#include <blockdb.h>
 #include <blockfilter.h>
 #include <chain.h>
 #include <chainparams.h>
diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -3,6 +3,7 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include <blockdb.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <coins.h>
diff --git a/src/test/util/blockfilter.cpp b/src/test/util/blockfilter.cpp
--- a/src/test/util/blockfilter.cpp
+++ b/src/test/util/blockfilter.cpp
@@ -4,6 +4,7 @@
 
 #include <test/util/blockfilter.h>
 
+#include <blockdb.h>
 #include <chainparams.h>
 #include <validation.h>
 
diff --git a/src/validation.h b/src/validation.h
--- a/src/validation.h
+++ b/src/validation.h
@@ -74,10 +74,6 @@
 static const unsigned int DEFAULT_MEMPOOL_EXPIRY = 336;
 /** The maximum size of a blk?????.dat file (since 0.8) */
 static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; // 128 MiB
-/** The pre-allocation chunk size for blk?????.dat files (since 0.8) */
-static const unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; // 16 MiB
-/** The pre-allocation chunk size for rev?????.dat files (since 0.8) */
-static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; // 1 MiB
 
 /** Maximum number of dedicated script-checking threads allowed */
 static const int MAX_SCRIPTCHECK_THREADS = 15;
@@ -322,16 +318,6 @@
                             const CBlockIndex **ppindex = nullptr)
     LOCKS_EXCLUDED(cs_main);
 
-/**
- * Open a block file (blk?????.dat).
- */
-FILE *OpenBlockFile(const FlatFilePos &pos, bool fReadOnly = false);
-
-/**
- * Translation to a filesystem path.
- */
-fs::path GetBlockPosFilename(const FlatFilePos &pos);
-
 /**
  * Import blocks from an external file.
  */
@@ -629,12 +615,6 @@
     ScriptExecutionMetrics GetScriptExecutionMetrics() const { return metrics; }
 };
 
-/** Functions for disk access for blocks */
-bool ReadBlockFromDisk(CBlock &block, const FlatFilePos &pos,
-                       const Consensus::Params &params);
-bool ReadBlockFromDisk(CBlock &block, const CBlockIndex *pindex,
-                       const Consensus::Params &params);
-
 bool UndoReadFromDisk(CBlockUndo &blockundo, const CBlockIndex *pindex);
 
 /** Functions for validating blocks and updating the block tree */
diff --git a/src/validation.cpp b/src/validation.cpp
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -8,6 +8,7 @@
 
 #include <arith_uint256.h>
 #include <avalanche/processor.h>
+#include <blockdb.h>
 #include <blockvalidity.h>
 #include <chainparams.h>
 #include <checkpoints.h>
@@ -172,9 +173,6 @@
                                    int nManualPruneHeight);
 static void FindFilesToPrune(std::set<int> &setFilesToPrune,
                              uint64_t nPruneAfterHeight);
-static FILE *OpenUndoFile(const FlatFilePos &pos, bool fReadOnly = false);
-static FlatFileSeq BlockFileSeq();
-static FlatFileSeq UndoFileSeq();
 static uint32_t GetNextBlockScriptFlags(const Consensus::Params &params,
                                         const CBlockIndex *pindex);
 
@@ -724,55 +722,6 @@
     return true;
 }
 
-bool ReadBlockFromDisk(CBlock &block, const FlatFilePos &pos,
-                       const Consensus::Params &params) {
-    block.SetNull();
-
-    // Open history file to read
-    CAutoFile filein(OpenBlockFile(pos, true), SER_DISK, CLIENT_VERSION);
-    if (filein.IsNull()) {
-        return error("ReadBlockFromDisk: OpenBlockFile failed for %s",
-                     pos.ToString());
-    }
-
-    // Read block
-    try {
-        filein >> block;
-    } catch (const std::exception &e) {
-        return error("%s: Deserialize or I/O error - %s at %s", __func__,
-                     e.what(), pos.ToString());
-    }
-
-    // Check the header
-    if (!CheckProofOfWork(block.GetHash(), block.nBits, params)) {
-        return error("ReadBlockFromDisk: Errors in block header at %s",
-                     pos.ToString());
-    }
-
-    return true;
-}
-
-bool ReadBlockFromDisk(CBlock &block, const CBlockIndex *pindex,
-                       const Consensus::Params &params) {
-    FlatFilePos blockPos;
-    {
-        LOCK(cs_main);
-        blockPos = pindex->GetBlockPos();
-    }
-
-    if (!ReadBlockFromDisk(block, blockPos, params)) {
-        return false;
-    }
-
-    if (block.GetHash() != pindex->GetBlockHash()) {
-        return error("ReadBlockFromDisk(CBlock&, CBlockIndex*): GetHash() "
-                     "doesn't match index for %s at %s",
-                     pindex->ToString(), pindex->GetBlockPos().ToString());
-    }
-
-    return true;
-}
-
 Amount GetBlockSubsidy(int nHeight, const Consensus::Params &consensusParams) {
     int halvings = nHeight / consensusParams.nSubsidyHalvingInterval;
     // Force block reward to zero when right shift is undefined.
@@ -4478,27 +4427,6 @@
              nLastBlockWeCanPrune, count);
 }
 
-static FlatFileSeq BlockFileSeq() {
-    return FlatFileSeq(GetBlocksDir(), "blk", BLOCKFILE_CHUNK_SIZE);
-}
-
-static FlatFileSeq UndoFileSeq() {
-    return FlatFileSeq(GetBlocksDir(), "rev", UNDOFILE_CHUNK_SIZE);
-}
-
-FILE *OpenBlockFile(const FlatFilePos &pos, bool fReadOnly) {
-    return BlockFileSeq().Open(pos, fReadOnly);
-}
-
-/** Open an undo file (rev?????.dat) */
-static FILE *OpenUndoFile(const FlatFilePos &pos, bool fReadOnly) {
-    return UndoFileSeq().Open(pos, fReadOnly);
-}
-
-fs::path GetBlockPosFilename(const FlatFilePos &pos) {
-    return BlockFileSeq().FileName(pos);
-}
-
 CBlockIndex *BlockManager::InsertBlockIndex(const BlockHash &hash) {
     AssertLockHeld(cs_main);
 
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -26,7 +26,6 @@
 #include <util/translation.h>
 #include <util/url.h>
 #include <util/validation.h>
-#include <validation.h>
 #include <wallet/coincontrol.h>
 #include <wallet/psbtwallet.h>
 #include <wallet/rpcwallet.h>
diff --git a/src/zmq/zmqpublishnotifier.cpp b/src/zmq/zmqpublishnotifier.cpp
--- a/src/zmq/zmqpublishnotifier.cpp
+++ b/src/zmq/zmqpublishnotifier.cpp
@@ -4,6 +4,7 @@
 
 #include <zmq/zmqpublishnotifier.h>
 
+#include <blockdb.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <config.h>
@@ -12,7 +13,6 @@
 #include <rpc/server.h>
 #include <streams.h>
 #include <util/system.h>
-#include <validation.h>
 
 #include <cstdarg>