John Rebchook of the Rocky Mountain News reports today ($770 Million for Five Office Buildings) that Chicago-based Callahan Capital Partners will be acquiring this week five major Downtown Denver office buildings for $770 million, including the Tabor Center on Block 068. If that wasn’t big enough news on its own, the article also reports that Callahan will begin construction later this year on the long-planned second office tower at the Tabor Center site.

Back in my November 4, 2006 blog, I reported on a story from the Denver Business Journal that Equity Office Properties, the current Tabor Center owner now selling to Callahan, was moving forward with plans to construct the second tower. With those plans in place, Callahan will be able to tweak the Equity design and move quickly into development review and permitting with the city and on to construction.

Callahan is debating whether to construct a 500,000 SF or 700,000 SF Tabor II tower. Based on my estimate of the second tower’s site dimensions, I’m guessing Tabor II would end up in the 27- to 38-story range. The existing Tabor I tower has 30 floors and 557,000 SF. Here’s an image showing the approximately location of the Tabor II site on Block 068:

The Tabor Center location is nearby several other proposed infill projects, including 1800 Larimer, the Cable Building hotel, and 1800 Market Residences, further strengthening the market vigor and appeal of the LoDo/CBD transition area.