close up of lake llyn idwal's lakeside rocks within cwm idwal's mountain range in

llyn idwal cwm glyderau mountains snowdonia landscape north wales nature serene mountain lake rugged terrain reflective waters rocky shoreline dramatic welsh scenery glacial valley hiking eryri national park adventure wilderness exploration untouched scenic tranquility iconic landscapes geological formations outdoor travel destination alpine beauty natural wonder pristine environment inspiration lush green hills cliffs peaceful escape reflections picturesque peaks rocks breathtaking views environmental conservation trails recreation historic heritage attractions retreat geology lakeside serenity bronze age arctic britain british