Machermore Castle is near Newton Stewart, in Dumfriesshire. It's a 16th-century castle on the banks of the River Cree, with about 30 acres of its own woodland. It's detached, obviously. The place sleeps up to twenty people, so it's for big groups. There are ten bedrooms and eight bathrooms, all of them en-suite.
It's got a five-star rating. That means it's very well finished, comfortable, and has everything you'd expect for a high-end stay. There's a big catering kitchen and a banqueting hall. People often book caterers for events here. There's also a games room, plenty of parking, and the garden and patio areas.
The location is the main thing. You're right at the gateway to the Galloway Forest Park. That's Britain's largest forest park, about 300 square miles. Good for walking, cycling, and mountain biking. It's also a Dark Sky Park, so the stargazing on a clear night is exceptional. The National Trust have a guide to the area's heritage if you're planning.
You're about twenty to thirty minutes' drive from a few interesting towns. Castle Douglas is known as a food town. Kirkcudbright is an artists' town with a nice harbour. Gatehouse of Fleet has a few more places to eat and drink. The coastline around here, the Machars, is rugged with little harbour villages like Portpatrick. You can drive down to the Mull of Galloway, the most southerly point in Scotland. The lighthouse there is open and the views are huge. The RSPB has a reserve nearby.
The nearest shop, pub, and restaurant are about a mile and a half away. The coast is about eight miles. There's local fishing and a golf course nearby.
Facilities: everything you'd need is included. Washing machine, dishwasher, WiFi, TV, woodburning stove. Bedding and towels are provided. They can provide a highchair. No pets.
Useful links for planning: Galloway Forest Park and National Trust for Scotland South West.