3 km sounds like too much to me. I don't think most people here would walk that far to do their shopping, especially in 30°C heat, mostly because we usually have small supermarkets all around.
I currently walk 500 m to my small neighbourhood supermarket when I just need to buy a few things and I don't recall ever living further away from some small supermaket. When I am running out of provisions, I take my car and go to a big hypermarket 7 km away. There are other hypermarkets closer by, even within walking distance (2.3 km), but that farther one is the one I like for doing a big shopping.
Of course, distance isn't the only factor. It's not the same 500 m in London or Amsterdam which are mostly flat than in the city where I live now, where the 500 m to my supermarket have gradients of up to 15 %.
3 km sounds like too much to me. I don't think most people here would walk that far to do their shopping, especially in 30°C heat, mostly because we usually have small supermarkets all around.
I currently walk 500 m to my small neighbourhood supermarket when I just need to buy a few things and I don't recall ever living further away from some small supermaket. When I am running out of provisions, I take my car and go to a big hypermarket 7 km away. There are other hypermarkets closer by, even within walking distance (2.3 km), but that farther one is the one I like for doing a big shopping.
Of course, distance isn't the only factor. It's not the same 500 m in London or Amsterdam which are mostly flat than in the city where I live now, where the 500 m to my supermarket have gradients of up to 15 %.