The Taff Trail (Welsh: Taith Taf) is a popular walking and cycle path that runs for 55 miles (89 km) between Cardiff Bay and Brecon in Wales. It is so named because it follows the course of the River Taff.
Tongwynlais - after passing underneath the A470 dual carriageway, the trail reaches the village of Tongwynlais. As well as shops, pubs, a café, and a cycle shop, it is home to the Gothic fantasy castle, Castell Coch. At Tongwynlais, the trail splits into two. The high-level route climbs the steep hill to Castell Coch, then up a very steep path (best avoided in muddy conditions), and along a forest track of sharp stones. The low-level route is tarmacked and runs below the castle, adjacent to Taff's Well railway station and then climbs steadily for 1.5 miles (2.4 km) along the former Rhymney Railway, until it rejoins the high-level route just before the Nantgarw bypass.
Here the route turns left off the main path, an easy turn to miss, and crosses the bypass, joining National Cycle Network Route 4 (known in Wales as the Celtic Trail). Route 4 stretches from London in the east to St David's in the west, and runs along with the Taff Trail as far as Pontypridd.
Pontypridd - the trail proceeds along the former Alexandra (Newport Docks) Docks & Railway Company line towards Rhydyfelin. At Rhydyfelin, the Trail emerges briefly to cross a minor road, before continuing through the Glyntaff Farm housing estate and passing along the length of Glyntaff Cemetery. After the cemetery, the Trail joins Cilfynydd Road. The former route continued along the road for half a mile, before leading into the northern end of Pontypridd town centre. However, the trail is now signposted to cross a pedestrian bridge and pass through Ynysangharad Park. At the northern exit from the park, users may wish to take a short (50 yards) detour to visit the Old Bridge in Pontypridd.