Yesterday, as part of a 35-person tour group, two of our group members were pick pocketed in the vicinity of the astronomical clock. This occurred after repeated alerts from our tour director and our local tour guide. Please note that when people say it is crowded in front of the clock, it is so crowded that it is difficult to lift your arms; and, everyone's attention is focused on the clock. This is a pick-pocket's dream. Carry only your daily monetary needs and use a money belt or lock your large amounts of cash and passport, etc. in your hotel safe.
Thanks for the info, will be there this summer and need to remember to stay alert.
Was this a Rick Steves tour?
This was not a Rick Steve's tour. And, I agree with George that the astronomical clock isn't particularly interesting. Nonetheless, it appears that all the tours converge in that one spot at the top of the hour. The learning lesson is that where there are crowds, there will be pickpockets.