Le Mans was an entirely different challenge in the 1920s.  J. D. Benjafield was a part of the Bentley team. This is his account of the 1925 event, two years before the Bentley factory squad made its breakthrough.

This, the greatest race for cars in touring trim, took place at Le Mans on June 20th, 1925, finishing 24 hours later. Arriving at the circuit six days before the race, one was immediately impressed by the forward state of the preparations, and, although the course was never officially closed, practice was proceeding more or less continuously night and day; one fears that the people whose houses abutted on the circuit enjoyed little sleep during this period, as most of the cars engaged had open exhausts, silencing regulations being noticeable by their absence.

Each lap of the circuit measures approximately 10 miles, and it is composed of a 4-mile more-or-less straight leg with a slight down grade and good tarred surface, followed by a right-angled turn, and then winding road, including a severe S-bend, after which it straightens out and runs down to the famous Pontlieue hairpin, where it joins up with the straight leg once more.