diff --git a/cmd/utils/history_test.go b/cmd/utils/history_test.go
index d4500be53..5a13f67aa 100644
--- a/cmd/utils/history_test.go
+++ b/cmd/utils/history_test.go
@@ -134,7 +134,7 @@ func TestHistoryImportAndExport(t *testing.T) {
 			for j := 0; it.Next(); j++ {
 				n := i*int(step) + j
 				if it.Error() != nil {
-					t.Fatalf("error reading block entry %d: %v", n, err)
+					t.Fatalf("error reading block entry %d: %v", n, it.Error())
 				}
 				block, receipts, err := it.BlockAndReceipts()
 				if err != nil {
diff --git a/internal/era/builder.go b/internal/era/builder.go
index be50355ee..9217c049f 100644
--- a/internal/era/builder.go
+++ b/internal/era/builder.go
@@ -49,7 +49,7 @@ import (
 //	CompressedBody     = { type: [0x04, 0x00], data: snappyFramed(rlp(body)) }
 //	CompressedReceipts = { type: [0x05, 0x00], data: snappyFramed(rlp(receipts)) }
 //	TotalDifficulty    = { type: [0x06, 0x00], data: uint256(header.total_difficulty) }
-//	Accumulator        = { type: [0x07, 0x00], data: accumulator-root }
+//	AccumulatorRoot    = { type: [0x07, 0x00], data: accumulator-root }
 //	BlockIndex         = { type: [0x32, 0x66], data: block-index }
 //
 // Accumulator is computed by constructing an SSZ list of header-records of length at most
@@ -64,8 +64,8 @@ import (
 //	block-index := starting-number | index | index | index ... | count
 //
 // starting-number is the first block number in the archive. Every index is a
-// defined relative to index's location in the file. The total number of block
-// entries in the file is recorded in count.
+// defined relative to beginning of the record. The total number of block
+// entries in the file is recorded with count.
 //
 // Due to the accumulator size limit of 8192, the maximum number of blocks in
 // an Era1 batch is also 8192.
@@ -115,12 +115,14 @@ func (b *Builder) Add(block *types.Block, receipts types.Receipts, td *big.Int)
 func (b *Builder) AddRLP(header, body, receipts []byte, number uint64, hash common.Hash, td, difficulty *big.Int) error {
 	// Write Era1 version entry before first block.
 	if b.startNum == nil {
-		if err := writeVersion(b.w); err != nil {
+		n, err := b.w.Write(TypeVersion, nil)
+		if err != nil {
 			return err
 		}
-		n := number
-		b.startNum = &n
+		startNum := number
+		b.startNum = &startNum
 		b.startTd = new(big.Int).Sub(td, difficulty)
+		b.written += n
 	}
 	if len(b.indexes) >= MaxEra1Size {
 		return fmt.Errorf("exceeds maximum batch size of %d", MaxEra1Size)
@@ -169,7 +171,7 @@ func (b *Builder) Finalize() (common.Hash, error) {
 		return common.Hash{}, fmt.Errorf("error writing accumulator: %w", err)
 	}
 	// Get beginning of index entry to calculate block relative offset.
-	base := int64(b.written + (3 * 8)) // skip e2store header (type, length) and start block
+	base := int64(b.written)
 
 	// Construct block index. Detailed format described in Builder
 	// documentation, but it is essentially encoded as:
@@ -186,7 +188,7 @@ func (b *Builder) Finalize() (common.Hash, error) {
 	// relative offset, the corresponding block can be quickly read by
 	// performing a seek relative to the current position.
 	for i, offset := range b.indexes {
-		relative := int64(offset) - (base + int64(i)*8)
+		relative := int64(offset) - base
 		binary.LittleEndian.PutUint64(index[8+i*8:], uint64(relative))
 	}
 	binary.LittleEndian.PutUint64(index[8+count*8:], uint64(count))
@@ -220,9 +222,3 @@ func (b *Builder) snappyWrite(typ uint16, in []byte) error {
 	}
 	return nil
 }
-
-// writeVersion writes a version entry to e2store.
-func writeVersion(w *e2store.Writer) error {
-	_, err := w.Write(TypeVersion, nil)
-	return err
-}
diff --git a/internal/era/era.go b/internal/era/era.go
index 38bebfced..a0e701b7e 100644
--- a/internal/era/era.go
+++ b/internal/era/era.go
@@ -221,9 +221,10 @@ func (e *Era) Count() uint64 {
 // is the absolute block number desired.
 func (e *Era) readOffset(n uint64) (int64, error) {
 	var (
-		firstIndex  = -8 - int64(e.m.count)*8               // size of count - index entries
-		indexOffset = int64(n-e.m.start) * 8                // desired index * size of indexes
-		offOffset   = e.m.length + firstIndex + indexOffset // offset of block offset
+		blockIndexRecordOffset = e.m.length - 24 - int64(e.m.count)*8 // skips start, count, and header
+		firstIndex             = blockIndexRecordOffset + 16          // first index after header / start-num
+		indexOffset            = int64(n-e.m.start) * 8               // desired index * size of indexes
+		offOffset              = firstIndex + indexOffset             // offset of block offset
 	)
 	e.mu.Lock()
 	defer e.mu.Unlock()
@@ -231,10 +232,10 @@ func (e *Era) readOffset(n uint64) (int64, error) {
 	if _, err := e.f.ReadAt(e.buf[:], offOffset); err != nil {
 		return 0, err
 	}
-	// Since the block offset is relative from its location + size of index
-	// value (8), we need to add it to it's offset to get the block's
-	// absolute offset.
-	return offOffset + 8 + int64(binary.LittleEndian.Uint64(e.buf[:])), nil
+	// Since the block offset is relative from the start of the block index record
+	// we need to add the record offset to it's offset to get the block's absolute
+	// offset.
+	return blockIndexRecordOffset + int64(binary.LittleEndian.Uint64(e.buf[:])), nil
 }
 
 // newReader returns a snappy.Reader for the e2store entry value at off.