Also does not work where you have estuaries and limited bridges.
Hope you had a good vacation.
Thinking further, even in a city grid you have one-way streets, parks, longer blocks, etc., which can make the real distance (by road) much further than "as the crow flies". So I'm not sure nn is really good for any such "close to me" analysis tool.
And yes thanks, had a great vacation. Miss the cool weather from my native state!