Look at Boulder Colorado which has an extensive network where many of the paths hug the creek running through the city.
The easiest place to start in most cities is to just build paths along rivers and streams that go beneath or above roads.
[1] https://en.wikipedia.org/wiki/Houten
Come visit!
>The design principle of separating cycling and walking from car traffic has been pushed to the limit. Houten is unique in this. Cycling comfort and safety are extremely high (optimal), even by Dutch standards. A large network of bike paths makes it convenient to cycle to various destinations and within the town the bike is the most popular means of transport. > The city of Houten is known as, nationally and internationally, and in growing interest from home and abroad, as the worlds best practical example for bicycle friendliness. A growing number of groups with politicians, developers, designers and students visit cycling city Houten for study purposes and inspiration.
This sort of thing is a big part of why places like Houten (and Odense - basically second or third tier cities with good infra but lower cost of living than capitals) are on our short list.