diff --git a/.changeset/new-kiwis-confess.md b/.changeset/new-kiwis-confess.md
new file mode 100644
index 0000000000..8816d1b758
--- /dev/null
+++ b/.changeset/new-kiwis-confess.md
@@ -0,0 +1,5 @@
+---
+"@remix-run/router": patch
+---
+
+Fix URL creation in Cloudflare Pages or other non-browser-environment
diff --git a/package.json b/package.json
index d359a2a285..d7b6afc2db 100644
--- a/package.json
+++ b/package.json
@@ -107,7 +107,7 @@
   },
   "filesize": {
     "packages/router/dist/router.umd.min.js": {
-      "none": "35 kB"
+      "none": "35.5 kB"
     },
     "packages/react-router/dist/react-router.production.min.js": {
       "none": "12.5 kB"
diff --git a/packages/router/history.ts b/packages/router/history.ts
index 56779c8f9d..e5117817b7 100644
--- a/packages/router/history.ts
+++ b/packages/router/history.ts
@@ -447,6 +447,20 @@ export function createHashHistory(
 //#region UTILS
 ////////////////////////////////////////////////////////////////////////////////
 
+/**
+ * @private
+ */
+export function invariant(value: boolean, message?: string): asserts value;
+export function invariant<T>(
+  value: T | null | undefined,
+  message?: string
+): asserts value is T;
+export function invariant(value: any, message?: string) {
+  if (value === false || value === null || typeof value === "undefined") {
+    throw new Error(message);
+  }
+}
+
 function warning(cond: any, message: string) {
   if (!cond) {
     // eslint-disable-next-line no-console
@@ -544,7 +558,7 @@ export function parsePath(path: string): Partial<Path> {
   return parsedPath;
 }
 
-export function createURL(location: Location | string): URL {
+export function createClientSideURL(location: Location | string): URL {
   // window.location.origin is "null" (the literal string value) in Firefox
   // under certain conditions, notably when serving from a local HTML file
   // See https://bugzilla.mozilla.org/show_bug.cgi?id=878297
@@ -553,8 +567,12 @@ export function createURL(location: Location | string): URL {
     typeof window.location !== "undefined" &&
     window.location.origin !== "null"
       ? window.location.origin
-      : "unknown://unknown";
+      : window.location.href;
   let href = typeof location === "string" ? location : createPath(location);
+  invariant(
+    base,
+    `No window.location.(origin|href) available to create URL for href: ${href}`
+  );
   return new URL(href, base);
 }
 
@@ -643,7 +661,9 @@ function getUrlBasedHistory(
     },
     encodeLocation(to) {
       // Encode a Location the same way window.location would
-      let url = createURL(typeof to === "string" ? to : createPath(to));
+      let url = createClientSideURL(
+        typeof to === "string" ? to : createPath(to)
+      );
       return {
         pathname: url.pathname,
         search: url.search,
diff --git a/packages/router/index.ts b/packages/router/index.ts
index f9739ba566..23bfca95b1 100644
--- a/packages/router/index.ts
+++ b/packages/router/index.ts
@@ -32,7 +32,6 @@ export {
   defer,
   generatePath,
   getToPathname,
-  invariant,
   isRouteErrorResponse,
   joinPaths,
   json,
@@ -59,13 +58,13 @@ export type {
   Path,
   To,
 } from "./history";
-
 export {
   Action,
   createBrowserHistory,
   createPath,
   createHashHistory,
   createMemoryHistory,
+  invariant,
   parsePath,
 } from "./history";
 
diff --git a/packages/router/router.ts b/packages/router/router.ts
index 7d3b1d3f76..8bd5ae9f55 100644
--- a/packages/router/router.ts
+++ b/packages/router/router.ts
@@ -3,7 +3,8 @@ import {
   Action as HistoryAction,
   createLocation,
   createPath,
-  createURL,
+  createClientSideURL,
+  invariant,
   parsePath,
 } from "./history";
 import type {
@@ -28,7 +29,6 @@ import {
   ResultType,
   convertRoutesToDataRoutes,
   getPathContributingMatches,
-  invariant,
   isRouteErrorResponse,
   joinPaths,
   matchRoutes,
@@ -913,7 +913,7 @@ export function createRouter(init: RouterInit): Router {
 
     // Create a controller/Request for this navigation
     pendingNavigationController = new AbortController();
-    let request = createRequest(
+    let request = createClientSideRequest(
       location,
       pendingNavigationController.signal,
       opts && opts.submission
@@ -954,7 +954,7 @@ export function createRouter(init: RouterInit): Router {
       loadingNavigation = navigation;
 
       // Create a GET request for the loaders
-      request = createRequest(request.url, request.signal);
+      request = new Request(request.url, { signal: request.signal });
     }
 
     // Call loaders
@@ -1299,7 +1299,11 @@ export function createRouter(init: RouterInit): Router {
 
     // Call the action for the fetcher
     let abortController = new AbortController();
-    let fetchRequest = createRequest(path, abortController.signal, submission);
+    let fetchRequest = createClientSideRequest(
+      path,
+      abortController.signal,
+      submission
+    );
     fetchControllers.set(key, abortController);
 
     let actionResult = await callLoaderOrAction(
@@ -1346,7 +1350,7 @@ export function createRouter(init: RouterInit): Router {
     // Start the data load for current matches, or the next location if we're
     // in the middle of a navigation
     let nextLocation = state.navigation.location || state.location;
-    let revalidationRequest = createRequest(
+    let revalidationRequest = createClientSideRequest(
       nextLocation,
       abortController.signal
     );
@@ -1501,7 +1505,7 @@ export function createRouter(init: RouterInit): Router {
 
     // Call the loader for this fetcher route match
     let abortController = new AbortController();
-    let fetchRequest = createRequest(path, abortController.signal);
+    let fetchRequest = createClientSideRequest(path, abortController.signal);
     fetchControllers.set(key, abortController);
     let result: DataResult = await callLoaderOrAction(
       "loader",
@@ -1675,7 +1679,7 @@ export function createRouter(init: RouterInit): Router {
       ...fetchersToLoad.map(([, href, match, fetchMatches]) =>
         callLoaderOrAction(
           "loader",
-          createRequest(href, request.signal),
+          createClientSideRequest(href, request.signal),
           match,
           fetchMatches,
           router.basename
@@ -2120,7 +2124,7 @@ export function unstable_createStaticHandler(
     if (!actionMatch.route.action) {
       let error = getInternalRouterError(405, {
         method: request.method,
-        pathname: createURL(request.url).pathname,
+        pathname: new URL(request.url).pathname,
         routeId: actionMatch.route.id,
       });
       if (isRouteRequest) {
@@ -2206,7 +2210,7 @@ export function unstable_createStaticHandler(
     }
 
     // Create a GET request for the loaders
-    let loaderRequest = createRequest(request.url, request.signal);
+    let loaderRequest = new Request(request.url, { signal: request.signal });
     let context = await loadRouteData(loaderRequest, matches);
 
     return {
@@ -2240,7 +2244,7 @@ export function unstable_createStaticHandler(
     if (isRouteRequest && !routeMatch?.route.loader) {
       throw getInternalRouterError(400, {
         method: request.method,
-        pathname: createURL(request.url).pathname,
+        pathname: new URL(request.url).pathname,
         routeId: routeMatch?.route.id,
       });
     }
@@ -2531,9 +2535,9 @@ function shouldRevalidateLoader(
   isRevalidationRequired: boolean,
   actionResult: DataResult | undefined
 ) {
-  let currentUrl = createURL(currentLocation);
+  let currentUrl = createClientSideURL(currentLocation);
   let currentParams = currentMatch.params;
-  let nextUrl = createURL(location);
+  let nextUrl = createClientSideURL(location);
   let nextParams = match.params;
 
   // This is the default implementation as to when we revalidate.  If the route
@@ -2624,7 +2628,10 @@ async function callLoaderOrAction(
       );
 
       // Check if this an external redirect that goes to a new origin
-      let external = createURL(location).origin !== createURL("/").origin;
+      let currentUrl = new URL(request.url);
+      let currentOrigin = currentUrl.origin;
+      let newOrigin = new URL(location, currentOrigin).origin;
+      let external = newOrigin !== currentOrigin;
 
       // Support relative routing in internal redirects
       if (!external) {
@@ -2632,8 +2639,11 @@ async function callLoaderOrAction(
         let routePathnames = getPathContributingMatches(activeMatches).map(
           (match) => match.pathnameBase
         );
-        let requestPath = createURL(request.url).pathname;
-        let resolvedLocation = resolveTo(location, routePathnames, requestPath);
+        let resolvedLocation = resolveTo(
+          location,
+          routePathnames,
+          currentUrl.pathname
+        );
         invariant(
           createPath(resolvedLocation),
           `Unable to resolve redirect location: ${location}`
@@ -2713,12 +2723,15 @@ async function callLoaderOrAction(
   return { type: ResultType.data, data: result };
 }
 
-function createRequest(
+// Utility method for creating the Request instances for loaders/actions during
+// client-side navigations and fetches.  During SSR we will always have a
+// Request instance from the static handler (query/queryRoute)
+function createClientSideRequest(
   location: string | Location,
   signal: AbortSignal,
   submission?: Submission
 ): Request {
-  let url = createURL(stripHashFromPath(location)).toString();
+  let url = createClientSideURL(stripHashFromPath(location)).toString();
   let init: RequestInit = { signal };
 
   if (submission) {
diff --git a/packages/router/utils.ts b/packages/router/utils.ts
index cd35742733..53c970f823 100644
--- a/packages/router/utils.ts
+++ b/packages/router/utils.ts
@@ -1,5 +1,5 @@
 import type { Location, Path, To } from "./history";
-import { parsePath } from "./history";
+import { invariant, parsePath } from "./history";
 
 /**
  * Map of routeId -> data returned from a loader/action/error
@@ -771,20 +771,6 @@ export function stripBasename(
   return pathname.slice(startIndex) || "/";
 }
 
-/**
- * @private
- */
-export function invariant(value: boolean, message?: string): asserts value;
-export function invariant<T>(
-  value: T | null | undefined,
-  message?: string
-): asserts value is T;
-export function invariant(value: any, message?: string) {
-  if (value === false || value === null || typeof value === "undefined") {
-    throw new Error(message);
-  }
-}
-
 /**
  * @private
  */