Funded by the Welsh European Funding Office, the year-long drive, which will run under the slogan 'trips with a difference', will promote the area as an activity holiday destination.
Golley Slater will promote activities such as hot-air ballooning and working-farm holidays, as well as restaurants, hotels and B&B accommodation.
A second campaign, entitled 'Carmarthenshire, where food comes to life', will showcase local produce.
Golley Slater will also encourage pubs, restaurants and hoteliers to sign up as members of the CTA.
The promotional drive, which starts later this month, will target local and national press, travel, food, business and culture titles.
CTA marketing and membership manager Nia Hale said: 'We hope the campaign will encourage the people of Wales to explore the rich culture and beautiful scenery that is on their doorstep, as well as attract new visitors from further afield.'