Downtown’s most distressed office buildings are also some of the region’s largest. Built during an oil and gas boom in the 1970s and 1980s, most are located in the Upper Downtown and Skyline Park areas, which had multiple blocks scraped to make room for taller buildings.

READ THE FULL PROJECT: At a crossroads: Downtown Denver is waiting for its rebound

Tenants are increasingly favoring smaller leases in the LoDo, Central Platte Valley and Union Station areas if they aren’t leaving for other districts. Denver has designated at least 30 of downtown’s towers as distressed, meaning they have a higher vacancy rate or have been emptied out for renovations or a new use. Click circles for details. Only buildings larger than 100,000 square feet are included.

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