The picture postcard Cott Inn at Dartington in South Devon has been put on the market by current owners David and Margaret Sorton, who plan to retire.
The Grade II-listed country inn and restaurant is believed to be England's longest licensed thatched property.
It was built during the reign of Edward II and has been a pub since 1320.
The inn - which has built up a reputation for good, locally-sourced food - enjoys a strong local trade that is boosted by influxes of tourists in the spring, summer and autumn.
It incorporates five en-suite letting bedrooms, a heavily-beamed traditional bar and lounge with seating for 55, a 24-seat restaurant, and two-bedroom owners' accommodation.
Outside, it has a paved terrace, a landscaped garden and a car park..
Property agent Bettesworth, which has been instructed to market the inn, described it as a "hugely successful business" with "superb" opportunities to develop trade further.
The current owners have held favourable discussions with the local planning department over adding more bedrooms in the garden area. They also have plans in place to enhance the trading areas by extending and altering the layout.
Cott Inn is held on a Greene King lease at a current rent of £75,000 per annum. Bettesworth is seeking offers of £299,950 for the leasehold interest.