Of all the Google Labs experiments to get the axe, City Tours is probably the most heartbreaking cut. The idea behind City Tours is that if you were visiting a new city, you could instantly plan a walking tour that plotted local attractions and kept the destination's hours of operation in mind with the suggestion. Here's Googler Matt Cutts showing City Tours in action.
City Tours never went beyond major tourist destinations, but it had amazing potential. You could map out a three day trip with around 10 destination suggestions per day, although the early versions made the mistake of using distance as the crow flies rather than actual walking distance, and it assumed you didn't need lunch, rest, flexible plans or transportation other than feet. Major cities had tour info, but smaller cities were still a little neglected. In other words, it needed a lot of work, but it had amazing potential.
You can still use Google Maps to plan your vacations. It may even be better, since you can change plans on the fly. If you've got a phone with a data plan, you can even get step by step walking directions. You can also see ratings and enhanced information about destinations through an attractions place page. Still, it was great to have a starting point. Hopefully Google will rethink this idea and figure out a way to make tourist maps easier than ever.