Its sturdy walls and modern cannon made difficult any attempt to storm the fortress.

Let those tall, sturdy walls he'd built this morning fall away already?

Don't let those sturdy walls of brick and glass fool you.

When the twins objected, he gave each a push in the direction of the sturdy walls.

Sally sobbed, her voice clearly heard by the others through the thin but sturdy walls of their prison.

The interior is now a park and little remains of the fort except for the sturdy outer walls.

So I focused on the sturdy walls of the compound and prayed straight to the black stones.

What is happening, they ask, to the once sturdy wall between reporters and political operatives?

I looked over his shoulder at the sturdy walls, the right angles, the roof that would keep out the rain.

You think of your house or apartment as a solid foundation surrounded by sturdy walls.