The estate comprises 5,000 acres (20 km2) of woodlands (known as Ashridge Forest), commons and chalk downland which supports a rich variety of wildlife.

[1] At the dissolution of the monasteries the priory was surrendered to the crown and King Henry VIII used it to house his children, namely Prince Edward and the Princesses Mary and Elizabeth.

[7] In July 1929 Ashridge opened by Stanley Baldwin as a College under the governance of the Bonar Law Memorial Trust (BLMT).

The foundation stone for the new house was laid by the 7th Earl's wife, Charlotte Catherine Anne, Countess of Bridgewater, on 25 October 1808, the 48th anniversary of the accession of George III of Great Britain.

It features a variety of casement windows including pointed arch and ogee lights typical of the early Gothic Revival style.

Before his untimely death, James Wyatt completed the north-facing front entrance and the central block, containing the state apartments and western courtyards.

[19] Inside the mansion are a number of richly decorated state rooms; of the interior features, only the hall, the staircase tower and the chapel are Gothic in design.

The high staircase hall features a stone stair with iron railing, surrounded by niches containing statues by Sir Richard Westmacott.

At the centre of the fan-vaulted ceiling is a large dial connected to the weather vane on the roof which displays the current wind direction.

The Brownlow Hall contains a giant frieze of the goddess Venus surrounded by putti with an armorial centrepiece and three early-Twentieth Century murals.

Redecoration of the interiors was commissioned by Lady Marian Alford and executed in the neoclassical style in 1855–63 by Sir Matthew Digby Wyatt, including a replica of Guido Reni's Aurora ceiling and aedicular door surrounds.

Repton presented many ideas in his Red Book for the estate in 1813, including a rosarie (or rosarium) and a "Monks' Garden" commemorating Ashridge's monastic heritage with a layout of grave-shaped flower beds.

[27] Ashridge Commons & Woods (grid reference SP975135) is a 640.1 hectare (1581.7 acre) Biological Site of Special Scientific Interest.

Scenes for Maleficent, Plotlands, Sleepy Hollow, Jonathan Creek and Harry Potter and the Goblet of Fire were filmed in Ashridge's Frithsden Beeches wood.

[36] In early 2023, English singer-songwriter Sam Smith released a music video for his song I'm Not Here to Make Friends, almost entirely shot in and outside the property.