concrete jungle
/ˌkɒŋ.kriːt ˈdʒʌŋ.ɡəl/noun
a city area full of large, ugly buildings and no green spaces
каменные джунгли
Русский аналог: «каменные джунгли»
Это скорее устойчивое сочетание, чем идиома.
“I grew up in a concrete jungle with no parks.”
“After a year in the concrete jungle, she moved to the countryside.”
“The new district is a concrete jungle.”