diff --git a/cmd/pebble/db.go b/cmd/pebble/db.go
index 6c05904ddc..ace743e5b8 100644
--- a/cmd/pebble/db.go
+++ b/cmd/pebble/db.go
@@ -76,6 +76,9 @@ func newPebbleDB(dir string) DB {
 			return 3
 		},
 	}
+	// In FormatColumnarBlocks (the value of FormatNewest at the time of
+	// writing), columnar blocks are only written if explicitly opted into.
+	opts.Experimental.EnableColumnarBlocks = func() bool { return true }
 
 	for i := 0; i < len(opts.Levels); i++ {
 		l := &opts.Levels[i]
diff --git a/docs/index.html b/docs/index.html
index 50046453ed..007090dbee 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -72,6 +72,8 @@
             (from 5d.4xlarge)</div>
         <div class="annotation" data-date="20240209">Changed AWS machine type
             (<a href="https://github.com/cockroachdb/cockroach/pull/117852">#117852</a>).</div>
+        <div class="annotation" data-date="20241015">Enabled columnar
+          blocks</div>
       </div>
       <div class="section rows">
         <div>