Malcolm Campbell becomes the first man to exceed 150 mph (241 km/h) on land. At Pendine Sands in Wales, he drives Sunbeam 350HP built by Sunbeam at a two-way average speed of 150.33 mph (242 km/h).

Major Sir Malcolm Campbell was a British racing motorist and motoring journalist. He gained the world speed record on land and on water at various times, using vehicles called Blue Bird, including a 1921 Grand Prix Sunbeam. His son, Donald Campbell, carried on the family tradition by holding both land speed and water speed records.

Pendine Sands is a 7-mile (11 km) beach on the shores of Carmarthen Bay on the south coast of Wales. It stretches west to east from Gilman Point to Laugharne Sands. The village of Pendine is close to the western end of the beach.

The Sunbeam 350HP is an aero-engined car built by the Sunbeam company in 1920, the first of several land speed record-breaking cars with aircraft engines.

Sunbeam Motor Car Company Limited was a British automobile manufacturer in operation between 1905 and 1934. Its works were at Moorfields in Blakenhall, a suburb of Wolverhampton in Staffordshire, now West Midlands. The Sunbeam name had originally been registered by John Marston in 1888 for his bicycle manufacturing business. Sunbeam motor car manufacture began in 1901. The motor business was sold to a newly incorporated Sunbeam Motor Car Company Limited in 1905 to separate it from Marston's pedal bicycle business; Sunbeam motorcycles were not made until 1912.

July 21 is the 202nd day of the year in the Gregorian calendar; 163 days remain until the end of the year.