| Wych Brook River Elfe, Red Brook, Worthenbury Brook | |
|---|---|
 The Wych Brook at Higher Wych | |
| Location | |
| Country | Wales, England |
| Counties | Wrexham County Borough, Cheshire, Shropshire |
| Physical characteristics | |
| Source | |
| • location | Fenn's Moss, Wrexham County Borough |
| • coordinates | 52°59′37″N 2°49′24″W / 52.99352°N 2.82339°W |
| Mouth | River Dee |
• location | near Shocklach |
• coordinates | 53°2′19″N 2°51′42″W / 53.03861°N 2.86167°W |
| Basin features | |
| Tributaries | |
| • left | Emral Brook |
The Wych Brook, Worthenbury Brook and Red Brook, formerly known as the River Elfe, is a tributary of the River Dee in England and Wales, forming part of both the historic and present-day border between the two countries. The stream forms part of the border between Cheshire and Shropshire in England to the east, and Wales, particularly the Maelor Saesneg (a detached portion of Historic Flintshire, now within Wrexham County Borough), to the west.