South-east of the town centre in the foothills, not far from the Clos-Lucé, lay a sunny field sheltered from the wind. Charles VIII acquired it in the late 15th century to establish an orchard and vegetable garden. Around 1498 he had a house built in which he set up his "architect of gardens" from Italy, Pacello da Mercogliano. The Château Gaillard, whose name originates from a gentleman in the Middle Ages, was also known as "Hôtel Champêtre", champêtre meaning rustic or country-style. Mercogliano landscaped the grounds into terraces and used it as a plant nursery for the royal garden in Amboise. According to popular belief, the first orange trees in France grew in this garden.

King Louis XII, also an admirer of Italian art, gave the house and estate to Mercogliano in 1505. Mercogliano then sold it in 1510 to René de Savoie, also known as "Le Bâtard" (the bastard) and brother of Louise de Savoie (mother of Francis I). The new owner extended the building to the west, but he died in Pavia in 1525, leaving the château to his descendants. In 1559 the estate was owned by Cardinal Charles of Lorraine, an influential figure, who extended and enhanced it further. The château then experienced a brief apogee, before changing hands many times.

This three-level building, built of rubble stone and limestone, is the earliest example of the Renaissance style in Amboise. It was built with a rectangular layout on a terrace close to the hillside. The façade is in a chequer pattern formed by two moulded cordons and a rich cornice, and the bays between windows and dormers. The windows are framed with Doric pilasters, and the door lintels are decorated with plant motifs. Alongside René de Savoie's coat of arms, numerous royal emblems illustrate its owners' allegiances to different kings. Inside, a monumental fireplace with a Renaissance frieze has been preserved.

The château's chapel is "hidden" into the hillside, beneath a terrace. Inside, the pilasters bear the coat of arms of René de Savoie and his wife. A shrine stands out from the wall, probably the work of an Italian artist. Its foliage, birds, and other motifs are reminiscent of the style of the Della Robbia family. A marble plaque confirms that the chapel was consecrated in 1515.