Here is a list of some of the oldest schools in the United Kingdom, ranked by their foundation year. Please note that this is not an exhaustive list, and there may be other schools with similar or earlier foundation years.

1. King’s School, Canterbury (597)
2. The King’s School, Rochester (604)
3. St. Peter’s School, York (627)
4. The King’s School, Ely (970)
5. The Cathedral School, Llandaff (1120)
6. The Perse School, Cambridge (1615)
7. The King’s School, Chester (1541)
8. St. Olave’s Grammar School, London (1571)
9. The Crypt School, Gloucester (1539)
10. King Edward’s School, Witley (1553)
11. King Edward’s School, Birmingham (1552)
12. The Grammar School at Leeds (1552)
13. Christ’s Hospital, Horsham (1552)
14. Gresham’s School, Holt (1555)
15. Royal Grammar School, Guildford (1509)
16. The Grammar School at Leicester (1519)
17. Brentwood School, Essex (1558)
18. Bedford School, Bedford (1552)
19. The Harvey Grammar School, Folkestone (1674)
20. Bristol Grammar School (1532)
21. St. Bees School, Cumbria (1583)
22. St. Albans School, Hertfordshire (948)
23. Norwich School (1096)
24. The King’s School, Gloucester (1541)
25. Repton School, Derbyshire (1557)

Again, please note that this is not a comprehensive list, but it gives you an idea of some of the oldest schools in the United Kingdom.