There's no precise definition of an 18-hour city, but it falls between 9-to-5 roll-up-the-sidewalk towns and 24/7 metropolises. ATCO Properties & Management SVP of finance and acquisitions Neil Adamson tells us Nashville is definitely one.

"Nashville has evolved into an 18-hour city," Neil says. "From what we're seeing in the market, the macro functions are right. For tenants, that means a lower cost of doing business, and for workers, a high quality of living for a lower cost. As a result, Downtown and the surrounding area is booming with cool, hip restaurants and new urban-style apartments, while office developers are also busy. For investors, it’s an exciting market to watch and participate in.”

Investors are indeed interested in 18-hour cities. According to a survey released by ULI and PwC earlier this year, "eight of the top ten cities identified by respondents as the most favorable for investment and development in 2016 are secondary cities, sometimes called 18-hour cities."

In order of interest to investors and commercial and residential builders, these eight are DFW, Austin, Charlotte, Seattle, Atlanta, Denver, Nashville and Portland. (San Francisco and LA were also in the top 10).

"Another factor is Nashville's a pro-business, low cost of business environment," Neil says. "All of that put together is driving multifamily, retail and office activity both in the CBD and key urban areas like The Gulch, Germantown and the West End." (Pictured: Whiskey Kitchen in The Gulch.)

ATCO is a New York-based investor that recently bolstered its investment division with the promotion of Ryan Huber and the appointment of Joao Casimiro, each as VP of acquisitions; Ryan has focused on acquisitions for the company’s Sponsor Capital Fund in its acquisition of CBD office buildings and retail properties in Austin, Nashville, Charlotte and other growing cities.