Llys Dedwydd is a stone cottage down the lane from the main square in Dolgellau. It's in the town, so you're right there for the shops and pubs.
It sleeps four. Two bedrooms, one bathroom. It's got a 4 Star rating. It's been done up nicely. The living room is a good size with a sofa and a TV. The kitchen has a breakfast bar. The back garden is enclosed, which is handy, and it gets the sun in the afternoon.
You're about a minute's walk from everything in Dolgellau. There's a co-op, some good pubs, and a few nice cafes. It's a proper Welsh market town.
For getting out, you're right on the edge of Snowdonia National Park. The Mawddach Trail is just down the hill for a flat walk or cycle along the estuary. Cader Idris is right there if you want a proper mountain day. The beaches at Fairbourne and Barmouth are about a twenty-minute drive away.
Facilities: there's a washing machine, WiFi, and bedding is included. There's bike storage if you need it. There's no cot listed but there is a highchair. No pets, sorry.
Useful links: Snowdonia National Park and Visit Wales.