I visited the latest administrative offices, recently moved to downtown Denver, yesterday. I've posted a few photos here;
rbefly's Album: Pentax HQ, Denver Colorado USA - PentaxForums.com
This building is located at 633 17th Street, the Northeast corner of 17th and California streets. The office is on the 26th floor, suite 2600.
Please note that these are the admin offices only, both repairs and warehouse operations are at different locations.
Since they just moved (from Boulder, Colorado) in October 2011, the space isn't fully set up and there was no receptionist on duty when I arrived. But two of the Admin staff were kind enough to greet me and took the time to answer my many questions.
There was no formal "Tour" but they did walk me through a conference room, other offices and allowed me to take photos of the reception area. They showed me the latest "Q" camera and we discussed the differences between their former space in Boulder and the earlier location in Englewood, Colorado many years ago.
I was told that visitors are welcome, but it is best to call or e-mail first to make sure someone is available to escort you around.
If your travel plans include Colorado, be sure to call and stop by here! It's just a block off the 16th street (free) shuttle and right in the heart of downtown Denver.
No, they didn't share any trade secrets or new product "insider" news, but it was a very enjoyable visit.
Ron