diff --git a/README.md b/README.md
index 7c74feb..30771df 100644
--- a/README.md
+++ b/README.md
@@ -28,6 +28,7 @@ the Ecosystem section of the new landing page.
 | `commit-check.github.io/getting-started/` | [commit-check.com/getting-started/](https://commit-check.com/getting-started/) |
 | `commit-check.github.io/blog/…` | [commit-check.com/blog/…](https://commit-check.com/blog/) — same paths |
 | `commit-check.github.io/projects/` | [commit-check.com/](https://commit-check.com/) |
+| `commit-check.github.io/commit-check/<page>.html` — the Sphinx docs up to v2.12 | the matching page, e.g. `configuration.html` → [/configuration/](https://commit-check.com/configuration/), `cli_args.html` → [/configuration/#command-line-arguments](https://commit-check.com/configuration/#command-line-arguments) |
 
 The redirects are generated by `scripts/build_redirects.py`, and `tests/`
 verifies the map still covers every URL the old site served. GitHub Pages has
diff --git a/netlify.toml b/netlify.toml
index b404d62..fab0c1a 100644
--- a/netlify.toml
+++ b/netlify.toml
@@ -24,6 +24,57 @@
   status = 301
   force = true
 
+# The Sphinx project docs that predate the mkdocs site (OLD_PROJECT_DOCS in
+# scripts/build_redirects.py). Anything else under /commit-check/ was an index
+# or README page, which the home page replaced.
+[[redirects]]
+  from = "/commit-check/cli_args.html"
+  to = "https://commit-check.com/configuration/#command-line-arguments"
+  status = 301
+  force = true
+
+[[redirects]]
+  from = "/commit-check/what-is-new.html"
+  to = "https://commit-check.com/changelog/#v200"
+  status = 301
+  force = true
+
+[[redirects]]
+  from = "/commit-check/configuration.html"
+  to = "https://commit-check.com/configuration/"
+  status = 301
+  force = true
+
+[[redirects]]
+  from = "/commit-check/example.html"
+  to = "https://commit-check.com/example/"
+  status = 301
+  force = true
+
+[[redirects]]
+  from = "/commit-check/migration.html"
+  to = "https://commit-check.com/migration/"
+  status = 301
+  force = true
+
+[[redirects]]
+  from = "/commit-check/troubleshoot.html"
+  to = "https://commit-check.com/troubleshoot/"
+  status = 301
+  force = true
+
+[[redirects]]
+  from = "/commit-check/changelog.html"
+  to = "https://commit-check.com/changelog/"
+  status = 301
+  force = true
+
+[[redirects]]
+  from = "/commit-check/*"
+  to = "https://commit-check.com/"
+  status = 301
+  force = true
+
 # Everything else kept its path on the new site, so the tail is carried across
 # unchanged. This also covers URLs the stub list does not enumerate.
 [[redirects]]
diff --git a/scripts/build_redirects.py b/scripts/build_redirects.py
index e9993d8..e3616c5 100644
--- a/scripts/build_redirects.py
+++ b/scripts/build_redirects.py
@@ -57,8 +57,33 @@
 
 REDIRECTS = {path: path for path in SAME_PATH} | {"/projects/": "/"}
 
+#: The project documentation that came before the mkdocs site: Sphinx pages the
+#: ``commit-check/commit-check`` repository published at
+#: ``commit-check.github.io/commit-check/<page>.html``. That project site is no
+#: longer published, so GitHub Pages serves those paths from *this* site — and
+#: without these they fell through to the 404 fallback and landed every reader
+#: on the home page. They are still linked from the README of every release up
+#: to v2.12 (and so from PyPI), from blog posts and from the Action's docs.
+#:
+#: The page list is the Sphinx ``docs/`` of v2.12.2, the last release built
+#: that way, plus ``cli_args.html``, which sphinx-argparse generated. Each maps
+#: to the page that took over its content; ``what-is-new`` was the v2.0.0
+#: release notes and ``cli_args`` the command-line reference.
+OLD_PROJECT_DOCS = {
+    "/commit-check/": "/",  # also serves /commit-check/index.html
+    "/commit-check/README.html": "/",
+    "/commit-check/cli_args.html": "/configuration/#command-line-arguments",
+    "/commit-check/configuration.html": "/configuration/",
+    "/commit-check/example.html": "/example/",
+    "/commit-check/migration.html": "/migration/",
+    "/commit-check/troubleshoot.html": "/troubleshoot/",
+    "/commit-check/changelog.html": "/changelog/",
+    "/commit-check/what-is-new.html": "/changelog/#v200",
+}
+
 # The fragment is carried across by the script: a reader following a deep link
-# into a page should keep their place. ``location.replace`` rather than
+# into a page should keep their place — unless the target already names its
+# own section, which a second "#" would break. ``location.replace`` rather than
 # ``location.href`` so the stub does not land in the back-button history and
 # trap them in a loop between the two sites.
 TEMPLATE = """<!doctype html>
@@ -69,7 +94,7 @@
 <title>Moved to commit-check.com</title>
 <link rel="canonical" href="{target}">
 <meta http-equiv="refresh" content="0; url={target}">
-<script>location.replace("{target}" + location.hash);</script>
+<script>var t = "{target}"; location.replace(t.indexOf("#") < 0 ? t + location.hash : t);</script>
 <style>
   body {{ font-family: system-ui, sans-serif; margin: 4rem auto; max-width: 34rem;
          padding: 0 1rem; line-height: 1.6; }}
@@ -88,9 +113,11 @@
 
 def main() -> int:
     site = Path(__file__).resolve().parent.parent / "site"
-    for old, new in REDIRECTS.items():
+    for old, new in (REDIRECTS | OLD_PROJECT_DOCS).items():
         target = NEW_SITE + new
-        page = site / old.strip("/") / "index.html"
+        # "/a/b/" is served from a/b/index.html; "/a/b.html" is the file itself.
+        rel = old.strip("/")
+        page = site / rel if rel.endswith(".html") else site / rel / "index.html"
         page.parent.mkdir(parents=True, exist_ok=True)
         page.write_text(TEMPLATE.format(target=target), encoding="utf-8")
 
@@ -105,7 +132,10 @@ def main() -> int:
     # directories whose names begin with an underscore.
     (site / ".nojekyll").write_text("", encoding="utf-8")
 
-    print(f"wrote {len(REDIRECTS)} redirects + 404 fallback to {site}")
+    print(
+        f"wrote {len(REDIRECTS)} site + {len(OLD_PROJECT_DOCS)} project-docs "
+        f"redirects + 404 fallback to {site}"
+    )
     return 0
 
 
diff --git a/tests/redirects_test.py b/tests/redirects_test.py
index 368e87b..cd03c0a 100644
--- a/tests/redirects_test.py
+++ b/tests/redirects_test.py
@@ -23,7 +23,7 @@
 ROOT = Path(__file__).resolve().parent.parent
 sys.path.insert(0, str(ROOT / "scripts"))
 
-from build_redirects import REDIRECTS  # noqa: E402
+from build_redirects import OLD_PROJECT_DOCS, REDIRECTS, main  # noqa: E402
 
 
 def _urls_the_old_site_served() -> set[str]:
@@ -67,3 +67,24 @@ def test_no_redirect_points_at_a_url_that_never_existed():
         "these redirects are for URLs the site does not serve:\n  "
         + "\n  ".join(invented)
     )
+
+
+def test_old_project_docs_get_stubs_at_their_own_paths(tmp_path, monkeypatch):
+    """The Sphinx pages are files (``cli_args.html``), not directories, and a
+    target that names a section must not get the reader's fragment appended."""
+    import build_redirects
+
+    monkeypatch.setattr(build_redirects, "__file__", str(tmp_path / "scripts" / "x.py"))
+    assert main() == 0
+    site = tmp_path / "site"
+    for old, new in OLD_PROJECT_DOCS.items():
+        rel = old.strip("/")
+        page = site / rel if rel.endswith(".html") else site / rel / "index.html"
+        html = page.read_text(encoding="utf-8")
+        assert f'href="https://commit-check.com{new}"' in html, old
+    assert "t.indexOf(\"#\") < 0" in (site / "commit-check" / "what-is-new.html").read_text()
+
+
+def test_old_project_docs_do_not_shadow_the_mkdocs_redirects():
+    """The two maps must stay disjoint, or one silently overwrites the other."""
+    assert not set(OLD_PROJECT_DOCS) & set(REDIRECTS)