diff --git a/docs/site/.gitignore b/docs/site/.gitignore
index 8336c7f1d7d..9b916be5cff 100644
--- a/docs/site/.gitignore
+++ b/docs/site/.gitignore
@@ -3,3 +3,5 @@
 /assets/vendor
 /sitemap.xml
 /sitemap.md
+/sitemap.tsv
+
diff --git a/docs/site/assets/js/build.mjs b/docs/site/assets/js/build.mjs
index c185a19c817..235c6973cc2 100644
--- a/docs/site/assets/js/build.mjs
+++ b/docs/site/assets/js/build.mjs
@@ -9,6 +9,8 @@ import { Readable } from "node:stream";
 
 const SKIP_THESE = /(node_modules|\.jekyll-cache|^sitemap.*)/;
 
+const SITE = "https://cldr.unicode.org";
+
 async function processFile(d, fullPath, out) {
   const f = await fs.readFile(fullPath, "utf-8");
   const m = matter(f);
@@ -42,11 +44,88 @@ async function traverse(d, out) {
   return Promise.all(promises);
 }
 
+/** replace a/b/c.md with a/b */
+function path2dir(p) {
+  const dir = p.split("/").slice(0, -1).join("/");
+  return dir;
+}
+
+/** replace a/b/c.md with a/b/c.html */
+function md2html(p) {
+  return p.replace(/\.md$/, ".html");
+}
+
+/** replace a/b/c.html with a/b/c.md */
+function html2md(p) {
+  return p.replace(/\.html$/, ".md");
+}
+
 /** replace a/b/c.md with a/b/c */
 function dropmd(p) {
   return p.replace(/\.md$/, "");
 }
 
+function tabs(n) {
+  let s = [];
+  for (let i = 0; i < n; i++) {
+    s.push("\t");
+  }
+  return s.join("");
+}
+
+function mkurl(p) {
+  return `${SITE}/${md2html(p)}`;
+}
+
+const coll = new Intl.Collator(["und"]);
+
+function writeSiteMapSheet({ all, allDirs }, path, outsheet) {
+  // write my index
+  function indexForPath(p) {
+    if (p === "") {
+      p = "index.md";
+    } else {
+      p = path2dir(p) + ".md";
+    }
+    return all.findIndex(({ fullPath }) => fullPath === p);
+  }
+  const myIndex = indexForPath(path);
+  if (myIndex === -1) {
+    throw Error(`Could not find index for ${path}`);
+  }
+  const { title, fullPath: indexPath } = all[myIndex];
+  // find how how much to indent.
+  // 'path' is '' or 'foo/' or 'foo/bar/baz/' at this point.
+  const slashes = path.replace(/[^\/]+/g, ""); // foo/bar/ => //
+  const indent = tabs(slashes.length); // number of slashes => number of tabs
+  outsheet.push(`${indent}${title}\t${mkurl(indexPath)}`);
+
+  // now, gather the children.
+  const children = all.filter(({ fullPath }) => {
+    if (fullPath === indexPath) return false; // no self-list.
+    const myDir = path2dir(fullPath);
+    // would this item be under our dir?
+    if (`${myDir}.md` === indexPath) return true;
+    // special case for odd /index subdir
+    if (indexPath === `index.md` && myDir === "") return true;
+    return false;
+  });
+
+  children.sort((a, b) => coll.compare(a.fullPath, b.fullPath));
+
+  children.forEach(({ title, fullPath }) => {
+    // if an index, recurse instead.
+    const baseName = dropmd(fullPath); // downloads.md -> downloads
+    if (allDirs.has(baseName)) {
+      // it's a non-leaf node, recurse.
+      writeSiteMapSheet({ all, allDirs }, `${baseName}/`, outsheet);
+    } else {
+      // write leaf (non-index) child pages
+      outsheet.push(`${indent}\t${title}\t${mkurl(fullPath)}`);
+    }
+  });
+}
+
 async function writeSiteMaps(out) {
   // simple list of links
   const links = await Promise.all(
@@ -58,15 +137,13 @@ async function writeSiteMaps(out) {
       };
     })
   );
-  const stream = new SitemapStream({ hostname: "https://cldr.unicode.org" });
+  const stream = new SitemapStream({ hostname: SITE });
   const data = (
     await streamToPromise(Readable.from(links).pipe(stream))
   ).toString();
   await fs.writeFile("./sitemap.xml", data, "utf-8");
-  console.log("Wrote sitemap.xml");
+  console.log(`Wrote sitemap.xml with ${links.length} entries`);
 
-  /*
-  const coll = new Intl.Collator(["und"]);
   const allSorted = [...out.all].sort((a, b) =>
     coll.compare(a.fullPath, b.fullPath)
   );
@@ -82,7 +159,24 @@ async function writeSiteMaps(out) {
     "utf-8"
   );
   console.log("Wrote sitemap.md");
-  */
+
+  // now, create sitemap.tsv by walking
+  const outsheet = [];
+  const allPaths = out.all.map(({ fullPath }) => fullPath);
+  // Find all 'directories' (ending with /)
+  const allDirs = new Set();
+  allPaths.forEach((p) => {
+    const segs = p.split("/").slice(0, -1); // ['', 'dir1']
+    for (let n = 0; n <= segs.length; n++) {
+      // add all parent paths, so: '', dir1, dir1/dir2 etc.
+      const subpath = segs.slice(0, n).join("/");
+      allDirs.add(subpath);
+    }
+  });
+
+  writeSiteMapSheet({ all: out.all, allDirs }, "", outsheet);
+  await fs.writeFile("./sitemap.tsv", outsheet.join("\n"), "utf-8");
+  console.log(`wrote sitemap.tsv with ${outsheet.length} entries`);
 }
 
 async function main() {