diff --git a/pkgs/development/python-modules/lomond/default.nix b/pkgs/development/python-modules/lomond/default.nix
index 58e560c43e6d..7df0b38d54fe 100644
--- a/pkgs/development/python-modules/lomond/default.nix
+++ b/pkgs/development/python-modules/lomond/default.nix
@@ -12,7 +12,6 @@
   freezegun,
   pytest-mock,
   pytestCheckHook,
-  tornado_4,
 }:
 
 buildPythonPackage rec {
@@ -38,7 +37,7 @@ buildPythonPackage rec {
     freezegun
     pytest-mock
     pytestCheckHook
-  ] ++ lib.optionals (pythonOlder "3.10") [ tornado_4 ];
+  ];
 
   disabledTests =
     [
@@ -51,7 +50,7 @@ buildPythonPackage rec {
       "test_that_on_ping_responds_with_pong"
     ];
 
-  disabledTestPaths = lib.optionals (pythonAtLeast "3.10") [
+  disabledTestPaths = [
     # requires tornado_4, which is not compatible with python3.10
     "tests/test_integration.py"
   ];
diff --git a/pkgs/development/python-modules/tornado/4.nix b/pkgs/development/python-modules/tornado/4.nix
deleted file mode 100644
index 0381e25d953e..000000000000
--- a/pkgs/development/python-modules/tornado/4.nix
+++ /dev/null
@@ -1,42 +0,0 @@
-{
-  lib,
-  unittestCheckHook,
-  buildPythonPackage,
-  fetchPypi,
-  fetchpatch,
-  isPy27,
-  pythonAtLeast,
-}:
-
-buildPythonPackage rec {
-  pname = "tornado";
-  version = "4.5.3";
-  disabled = isPy27 || pythonAtLeast "3.10";
-
-  src = fetchPypi {
-    inherit pname version;
-    sha256 = "02jzd23l4r6fswmwxaica9ldlyc2p6q8dk6dyff7j58fmdzf853d";
-  };
-
-  patches = [
-    (fetchpatch {
-      name = "CVE-2023-28370.patch";
-      url = "https://github.com/tornadoweb/tornado/commit/32ad07c54e607839273b4e1819c347f5c8976b2f.patch";
-      hash = "sha256-2dpPHkNThOaZD8T2g1vb/I5WYZ/vy/t690539uprJyc=";
-    })
-  ];
-
-  nativeCheckInputs = [ unittestCheckHook ];
-
-  # We specify the name of the test files to prevent
-  # https://github.com/NixOS/nixpkgs/issues/14634
-  unittestFlagsArray = [ "*_test.py" ];
-
-  __darwinAllowLocalNetworking = true;
-
-  meta = {
-    description = "Web framework and asynchronous networking library";
-    homepage = "https://www.tornadoweb.org/";
-    license = lib.licenses.asl20;
-  };
-}
diff --git a/pkgs/top-level/python-aliases.nix b/pkgs/top-level/python-aliases.nix
index 8bd8f32db7a3..514ce622aa28 100644
--- a/pkgs/top-level/python-aliases.nix
+++ b/pkgs/top-level/python-aliases.nix
@@ -689,6 +689,7 @@ mapAliases ({
   thumborPexif = throw "thumborPexif has been removed, because it was unused."; # added 2024-01-07
   tissue = throw "tissue has been removed, because it is archived since October 2022"; # added 2024-07-27
   torchgpipe = throw "torchgpipe has been removed, because it appears unmaintained and Pytorch now includes pipeline parallelism support"; # added 2024-05-18
+  tornado_4 = throw "tornado_4 has been removed, use tornado instead"; # added 2025-01-13
   torrent_parser = torrent-parser; # added 2023-11-04
   transip = throw "transip has been removed because it is no longer maintained. TransIP SOAP V5 API was marked as deprecated"; # added 2023-02-27
   py-tree-sitter = throw "Was merged with tree-sitter."; # added 2024-03-20
diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 851b3f9c7d5b..b02a0133252a 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -16327,9 +16327,6 @@ self: super: with self; {
 
   tornado = callPackage ../development/python-modules/tornado { };
 
-  # Used by circus and grab-site, 2020-08-29
-  tornado_4 = callPackage ../development/python-modules/tornado/4.nix { };
-
   # Used by streamlit, 2021-01-29
   tornado_5 = callPackage ../development/python-modules/tornado/5.nix { };