Sharpen your brain with this collection of 101 quick-fire puzzles, produced by the Bletchley Park Trust. Bletchley Park was the British codebreaking HQ during World War II, gathering together the most brilliant problem-solving minds in the country. Follow in the footsteps of these men and women, puzzling through a variety of popular challenges. These include: . Number crunch . One to nine . Isolate . Pyramid plus Some of these puzzles feature beginner, intermediate and advanced solutions so you can tailor it to your own abilities. You can also fill in your finishing times on each page, and watch as your speed improves This book's 1940s cover design is reminiscent of wartime Britain and makes a wonderful gift. ABOUT THE SERIES: This book forms part of a series of puzzles books produced by the Bletchley Park Trust, a vibrant and fascinating heritage site celebrating the World War II codebreakers who were stationed there. Sales of this book support its running.