They were excavated between 1748 and 1752 for Francis Dashwood, 11th Baron le Despencer (2nd Baronet), founder of the Society of Dilettanti and co-founder of the Hellfire Club, whose meetings were held in the caves.

The unusual design of the caves was much inspired by Sir Francis Dashwood's visits to Italy, Greece, Turkey, Syria and other areas of the Ottoman Empire during his Grand Tour.

[2] In Greek mythology, the River Styx separated the mortal world from Hades, and the subterranean position of the Inner Temple directly beneath St Lawrence's Church was supposed to signify Heaven and Hell.

The club motto was Fais ce que tu voudras (Do what thou wilt), a philosophy of life associated with François Rabelais's fictional abbey at Thélème[4][5] and later used by Aleister Crowley.

According to Horace Walpole, the members' "practice was rigorously pagan: Bacchus and Venus were the deities to whom they almost publicly sacrificed; and the nymphs and the hogsheads that were laid in against the festivals of this new church, sufficiently informed the neighbourhood of the complexion of those hermits."

[10] The tours take visitors along passages which extend over 0.25 miles (400 m) underground past a series of chambers small to the Banqueting Hall and then to the so-called River Styx and the Inner Temple.