be (as) solid as a rock

To be stable, sturdy, and reliable. They've been married for 50 years, so their relationship has to be solid as a rock. That table must be as solid as a rock to withstand the ceiling collapse with hardly a scratch.

Common Names:

Name	Pronounced	Usage
Kern	[kə:n]
Sierra	see-ER-ə	English (Modern)
Margareta	mahr-gah-RE-tah (German), MAHR-gah-re-tah (Finnish)	German, Swedish, Norwegian, Danish, Romanian, Slovene, Dutch, Finnish, Croatian
Innocent	IN-ə-sənt (English)	History
Aphra	-	Various
Aysel	-	Turkish, Azerbaijani