Cyrn y Brain is a hill located near Llangollen in Wales. If you're planning to walk up to Cyrn y Brain from the Ponderosa, a great starting point is a route that starts from the Ponderosa Cafe, which is a popular spot along the Horseshoe Pass road. Cyrn y Brain is one of the Welsh Marilyns.

Here's a general description of the walk:

1. Starting Point - Ponderosa Cafe: Begin your walk from the Ponderosa Cafe, located on the Horseshoe Pass road. The cafe is a well-known landmark in the area and offers panoramic views.

2. Ascend Toward Cyrn y Brain: As you continue on the path, you'll likely start ascending towards Cyrn y Brain. The path may involve uphill sections, and you'll be treated to scenic views of the surrounding countryside.

3. Enjoy the Views: Along the way, take the opportunity to enjoy the stunning views of the Dee Valley and the hills around Llangollen. Depending on the time of year, the landscape may be dotted with heather and other flora.

4. Reach the Summit of Cyrn y Brain: The walk will eventually lead you to the summit of Cyrn y Brain. Once there, you can take in the panoramic views, which may include the Berwyn Mountains and other nearby hills.

5. Return Route: After enjoying the summit, you can retrace your steps or follow an alternative route for your descent back to the Ponderosa Cafe.

Continuing North will bring you to the Offa's Dyke Path. The Offa's Dyke Path is a long-distance trail that follows the ancient earthwork of Offa's Dyke.

Please note that walking conditions, paths, and routes can change, so it's advisable to check local maps, trail guides, or obtain up-to-date information from local authorities or walking organizations before embarking on the hike. Additionally, consider the weather conditions and ensure you are adequately prepared for the walk.