Karen Van Lengen and James Welty created a multimedia installation to encourage visitors to experience buildings like Grand Central Terminal not only through their eyes, but also their ears. Hansi Lo Wang/NPR hide caption

itoggle caption Hansi Lo Wang/NPR

On the outskirts of Rome is a mile-long stretch of unfinished elevated track for a tramline. Work stopped in the mid-1990s. Under the guidance of Renzo Piano, architects are turning it into an elevated park. Courtesy of the G124 Group hide caption

itoggle caption Courtesy of the G124 Group

Jay Austin's tiny house in Washington, D.C., has 10-foot ceilings, a loft bed over the bathroom and a galley-style kitchen. Franklyn Cater/NPR hide caption

itoggle caption Franklyn Cater/NPR

Alfafar, a suburb of Valencia, Spain, is suffering from a poor economy and high unemployment. A quarter of homes are abandoned. Here, a cafe is still open on the ground floor of an abandoned municipal building in Alfafar's Orba neighborhood, but upper floors used to house shops. A pair of Spanish architects hopes to revitalize the high-density housing in this working-class area. Lauren Frayer/NPR hide caption

itoggle caption Lauren Frayer/NPR

Kathy Van Sluyters (left), Barbara Carr and Colleen Dickinson chat on a recently finished sidewalk across from Wildflower Terrace, a mixed-income apartment building in the Mueller development for people ages 55 and over. Julia Robinson for NPR hide caption

itoggle caption Julia Robinson for NPR

Solar Sunflowers, an art installation, greets visitors to Mueller's commercial and retail hub off of Interstate 35. The panels power a nightly light display and return power to the grid. When the development is complete, five miles of granite trails will connect the residents to its commercial and retail hubs. Julia Robinson for NPR hide caption

itoggle caption Julia Robinson for NPR

A resident of Lathrop Homes leaves one of the few occupied buildings in the development. The city wants to redevelop the public housing as mixed use, and offered vouchers to encourage residents to relocate. Cheryl Corley/NPR hide caption

itoggle caption Cheryl Corley/NPR

Icehotel is located 120 miles above the Arctic Circle. The temperature outside is well below zero, but inside the hotel — while still, of course, below freezing — it's much warmer, hovering in the low 20s. Ari Shapiro/NPR hide caption

itoggle caption Ari Shapiro/NPR

The broadcast tower at Alexanderplatz looms over the city center. A crossing point of tourists, commuters, shoppers, lovers, artists and bums, Alexanderplatz was rebuilt by the communist authorities of former East Germany in the 1960s. Today, it's a popular gathering place in the reunified city. Sean Gallup/Getty Images hide caption

itoggle caption Sean Gallup/Getty Images

The Wilshire Boulevard Temple (pictured above circa 1939) was dedicated 85 years ago in 1929. Rabbi Steve Leder says, "This was the Los Angeles Jewish community's statement to itself — and to the majoritarian culture that surrounded it — that 'We are here, and we are prepared to be a great cultural and religious and civic force in our community.' " Courtesy Los Angeles Public Library hide caption

itoggle caption Courtesy Los Angeles Public Library

Interns who host tours on Capitol Hill, stopping at sites like the small Senate rotunda, don't always have their facts straight. The Architect of the Capitol hide caption

itoggle caption The Architect of the Capitol

At the center of Yangon, the city's colonial heritage, Buddhist faith and emerging modern face are visible in a single block. Frank Langfitt/NPR hide caption

itoggle caption Frank Langfitt/NPR

Couples stand on the Pont des Arts, Paris' iconic footbridge over the Seine river, where thousands upon thousands of padlocks bearing love messages are attached to the railing, on Aug. 30, 2013. Patrick Kovarik/AFP/Getty Images hide caption

itoggle caption Patrick Kovarik/AFP/Getty Images