diff --git a/.gitignore b/.gitignore
index 04dfa7f..edf9e06 100644
--- a/.gitignore
+++ b/.gitignore
@@ -158,8 +158,6 @@ dmypy.json
 # Cython debug symbols
 cython_debug/
 
-/book/_build
-
 # PyCharm
 #  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
 #  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore