Los Angeles Tallest Tower: Wilshire Grand A new skyscraper has been rising in the past two months that, when finished in 2017, will be the tallest building west of the Mississippi. The 73-story Wilshire Grand office-hotel complex in downtown Los Angeles features the latest in fire and earthquake safety. It’s the first in a series of planned high-rises downtown after years of almost no building. Here are some key features. Jeff Goertzen's graphic shows the key architectural features.