Leiston Abbey was northwest of the current town; its picturesque ruins are a popular tourist stop.
Leiston thrived in the late 19th and early 20th centuries as a manufacturing town dominated by the Richard Garrett Works (the "Leiston Works"). This firm made steam tractors and a huge variety of cast and machined metal products, including munitions during the World Wars. The works are closed now, and there is a large museum, the Long Shop Museum (http://gazeteer.interdart.co.uk/east/visit/LSMUSE.htm ), showing the history, vehicles and products of the Works.
During World War II, the Leiston airbase, west of the town, sent American and British fighter squadrons to fight the Germans. Famous test pilot and fighter ace Chuck Yaeger (who, later, first broke the sound barrier) flew out of Leiston.
Since the 1960s, Leiston became famous outside the UK as the home of the Summerhill School, founded by A. S. Neill in the 1920s, which was the first major "free school", referring to freedom in education. Children are not required to attend classes, and discipline is given by student self-government meetings. Summerhill has inspired a large "free school" movement, and more recently "Democratic Schools", in several countries. The school occupies the former mansion of Richard Garrett, owner of the Leiston Works.
The Leiston High Street serves as the business and market hub of the surrounding agricultural district, and as an entry for tourists visiting the nearby towns of Aldeburgh, Snape and Thorpeness. The town square has a Post Office, banks, shops and pubs. The town government includes nearby Sizewell on the seacoast, site of a nuclear power plant. The adjoining village of Aldringham is officially associated with more distant Thorpe (Thorpeness) rather than with Leiston. Leiston lost its railway connection in the 1960s and is now served by rural buses.
The Leiston Picture House (recently renamed the Leiston Film Theater), a half-timbered building with street front shops, is the oldest cinema (movie theater) built as such in all of Suffolk.
The town has a traditional church (Church of England), St. Margaret's with an ancient tower and an unusual 19th Century nave. In additon there are Roman Catholic and baptist churches at the edge of the town.
The people of Leiston used to speak with a heavy rural East-Anglian accent, but this lessened in the last half of the 20th century.