Smartest one I ever knew was my dog Digger, she was
a Blue Heeler/Aussy Shepard. Very intelligent.
My shop gate was on wheels and instead of just pushing
it open, she would put her paw on the wheel and roll it
open. Digger, miss you girl.
The smartest dogs I have known have all been at least part Heeler or Aussie- the best and smartest dog I ever had was 1/2 basset, 1/4 heeler, and 1/4 catahoula leopard. The Frumious Bandersnatch (Bander). She was simply amazing. Lived a long live, and died in 2004- we miss her and talk about her to this day.