World’s oldest working digital computer

Harwell Dekatron Witch Computer

The Harwell Dekatron WITCH has been rebuilt and rebooted at The National Museum of Computing in England, making it the world’s oldest working digital computer.

The 2.5 tonne, 1951 computer from Harwell with its 828 flashing Dekatron valves, 480 relays and a bank of paper tape readers will clatter back into action in the presence of two of the original designers, one of its first users and many others who have admired it at different times during its remarkable history.

If you’re a computer geek and get the chance to visit Bletchley Park, make sure you don’t overlook the museum. I had the opportunity to visit a couple years ago — I had no idea it was there, and probably could’ve devoted another day to it.