Cardiff, the capital of Wales, is a popular tourist destination known for its Welsh culture, festivals, shopping, and five castles surrounding the city. The document recommends exploring attractions in Cardiff like Bute Park in the city center and the Dyffryn Gardens, which features restored 100-year-old buildings and 55 acres of gardens. It suggests staying at Quay Serviced Apartments near these sites, which offer amenities like kitchens, more space, and appliances, making them a reasonable alternative to hotels.