What is Slow Travel? The concept stems from the Slow Food movement, which began in the 1980s in response to the increasing globalization of production, processing, and distribution of food, especially the proliferation of fast food restaurants at the time. Slow Travel also forms part of the larger Slow Movement, which emphasizes more local connections that can only emerge by slowing down the pace of life.
There is no specific methodology to Slow Travel. Principles include environmental sustainability, local sourcing of products and services, and a greater focus on your surroundings and the people who call the area home. For some people it may mean a stay with a local family, for others it might mean circumnavigating the globe without taking a plane, as depicted in the book "Only Planet: A Flight-free Adventure Around the World;" by Ed Gillespie.
Increasingly, we plan our trips at a much slower pace. I no longer feel the need to create a "must-see/do" list for which all the boxes must be checked. We are much happier now spending a week or two in one location and enjoying the local atmosphere, the weekly market, or a favorite local hangout on a Thursday night. Recent examples include a three week stay in South Africa, and our slow-paced road trips through the US and Canada.
It also doesn't matter if you have three days, three weeks, or three months.... Slow travel is about enjoying the moment and making an effort to establish local connections. A search on the term will give you more information, including companies offering a slow travel experience.
A few sources of information that I find helpful when thinking about slow travel:
Slow Movement - Includes information on slow travel.
Culturetrip - Great site with many articles about local experiences.
Traveling Bytes - Information about longer journeys, living in a location for a period of time, etc.