Across
- 3. Geiger Counter measurement (9)
- 7. A group of crows (6)
- 11. 1989 Snickers bar (8)
- 13. Swiss currency (5)
- 15. Setting of novel and film The Martian (4)
- 16. Affirming in Yorkshire (3)
- 17. Argentinian football captain (5)
- 18. Andy Murray's Wimbledon wins (3)
- 20. University attended by King Charles (9)
- 22. Famous William who wrote The Tyger and London (5)
- 23. Sn in the Periodic Table (3)
- 24. Strongest muscle in the human body (3)
Down
- 1. Nautical (9)
- 2. The Eternal City (4)
- 4. Largest US state (6)
- 5. Location of Mount Kilimanjaro (8)
- 6. The birthplace of pizza (6)
- 8. Mythical equine creature (7)
- 9. Trial run, test ... (5)
- 10. England's smallest county (7)
- 12. Jumping fish favoured by bears (6)
- 14. (Frankie) Ascot champion (7)
- 19. Bright sour fruit (5)
- 21. Irish isles (4)