It's called Hotspur View and it's in Alnwick town centre. The location is the main thing. You're a couple of minutes' walk from the market square, the castle gates, shops, and a few decent pubs. You can leave the car.
It's a terrace house that sleeps four. Two bedrooms upstairs, one king and one twin, and one bathroom. It's a 4 Star place, so it's comfortable and well looked after. There's a bit of a slope to the street, so the front door is up nine steps. There's also a ramp round the back if steps are a problem. The garden out the back is enclosed, which is handy.
Inside, it's straightforward. The living room is at the front. The kitchen and dining area are at the back, with doors out to the garden. It's got what you'd need: a dishwasher, washing machine, WiFi. Bedding and towels are included. You can bring one dog.
You're right by Alnwick Castle. It's worth a visit. The gardens are good too, especially for kids. The beach at Alnmouth is ten minutes in the car. It's a nice, wide sandy beach.
If you drive for about twenty minutes north, you get to Seahouses. You can get boat trips from there out to the Farne Islands for the seabirds and seals. Bamburgh Castle is just a bit further up the coast. Heading west, you're into the Northumberland National Park for walking.
Useful links if you're planning: Northumberland National Park and Northumberland Coast.