Portnall Park is in Virginia Water, Surrey, on Bagshot road, three miles (5 km) from Egham, and 21 miles from London.
A house was built at Potnalls, Potenall, Portenall, or Portnall Park by c. 1770. In 1804 Rev. Thomas Bisse (c1754-1828) exchanged it for some land at Tite Hill, Egham (probably land that had belonged to his wife's aunt Lydia Challoner (died 1803) with David Jebb, the younger son of Dr. John Jebb, Dean of Cashel (c1706-1787), and elder brother of John Jebb (reformer).
Bisse extended the mansion, as did the son, Colonel Bisse-Challoner (1788–1872), after 1828.
This is how Prosser described it in 1828: 'The park, comprising nearly four hundred acres, is beautifully undulated, and diversified with timber and flourishing plantations, through which extensive gravel walks and green rides are formed ; in well-chosen situations are seats and rustic retreats, commanding extensive and beautifully varied views over the Surrey hills on the one side, and over the far-famed lake of Virginia Water on the other.
The entrance lodge is built in a peculiarly elegant style, and the approach to the house is about three quarters of a mile through some thriving plantations. The gardens and farm to the south-west of the house are lately erected on a very convenient and elegant plan.'
Col. Challoner married, secondly, on 6 January 1859, Henrietta Emma Helena De Salis (1824–1863) third surviving daughter of Count de Salis. In 1872 Col. Challoner died and his estate passed to his second wife's youngest brother, Rev. Henry Jerome de Salis (d.1915). According to Henry Jerome's second son Cecil in 1872 Portnall was staffed by three men in the house; two in the stables; six or seven men in the garden; nine or 10 maids in the house; and four or five men on the farm [which was c600 acres].
On his death the life interest passed to Henry Jerome's eldest son, Rodolph (died 1931) (the youngest son was Charles Fane de Salis). He soon had the house on the market and after a brief struggle with his next brother it was eventually alienated and sold in 1923 to golf course pioneer and property developer W.G. Tarrant now of Wentworth Estate fame, for £15,000.