Welcome to the official audio companion to the Innovation Trail, a walking tour in Boston and Cambridge, Massachusetts that takes you across roughly two miles of dense urban streetscape and 400 years of scientific, technical, medical, and entrepreneurial advances. With the help of guide and narrator Carmichael Roberts and a galaxy of guest experts and tech celebrities, you'll learn about the people, ideas, and inventions — from the telephone to messenger RNA vaccines — that have long set Boston and Cambridge apart as world capitals of innovation. Most visitors start walking the Innovation Trail at 30 School Street in Boston, near the Park Street T stop. If you're accessing this guide through a podcast player, you'll see that the segments start there with "Patent Pioneer" and proceed west to Cambridge. (See http://theinnovationtrail.org for an interactive map.) But you can also begin the Trail from the Cambridge side, at 810 Main Street, and start with "The Last Candy Factory" episode and go in reverse order! The names of each stop on this guide correspond to those on our website, so you can also start the Trail at any stop, and walk as much as you have time for. The Trail includes four museums with regular operating hours, and we encourage you to stop in and explore any of them that pique your interest. Produced by Wade Roush: https://www.waderoush.com