Tweed Cottage is in Alnwick, just off the main street. It's an end-of-terrace house, so it's quiet. You can walk into town in a couple of minutes.
It sleeps four. Two bedrooms and one bathroom upstairs. It's got a 3 Star rating, so it's comfortable and clean, not luxurious. The stairs are a typical cottage staircase, so mind your head.
There's a pub and a restaurant about 500 yards away. For supermarkets and other shops, you just walk into town.
You're right by Alnwick Castle and the Alnwick Garden. Both are worth a visit. The coast is about four miles away. You can drive to Bamburgh Castle, which is impressive, or go to Seahouses for boat trips out to the Farne Islands. A bit further north is Holy Island, but you have to check the tide times for the causeway.
Newcastle is less than an hour's drive south if you want a city day. Edinburgh is about an hour and a half north.
For facilities, you've got a washing machine, a cot and a highchair if you need them, bedding and towels are included, and there's parking for one car on site. You can bring one well-behaved dog.
If you're planning trips out: Northumberland Coast National Landscape and National Trust North East have good information.