There was a huge glass ceiling or, really, actually it was a concrete ceiling, for women drummers.

FORBES: Female CEO Series: Tena Clark Drums Up the Next Phase of Her Career

Our next attempt to tackle the concrete ceiling problem will be to experiment with another new feature that comes with Airport Extreme: wireless bridging.

FORBES: Apple's Airport Meets The Concrete

The culprit, we concluded, was the room's thick concrete ceiling.

FORBES: Apple's Airport Meets The Concrete

The ceiling over it was again two feet of concrete and then eight feet of earth.

CNN: SHARE THIS

In August 2011, Speth and his chief engineer finally broke through more than two meters of earth and reinforced concrete and the shelter's 278-millimeter-thick ceiling to emerge into a 40-square-meter space, divided into five interconnecting rooms by heavy metals doors.

CNN: Vietnam War bunker reopened under luxury hotel

The floors throughout are a polished gray concrete and the walls are white, while light floods in through the floor-to-ceiling windows.

WSJ: Striking Gold in the Backyard