Something a bit different…
…I rode this on a snowy day in March 2018 (when it felt safer than heading out to the lanes). It visits all the parks and other spaces looked after by Royal Parks (taking in a few republican parks along the way!).
A total of about 92km. Some of the links are OK (Q1 and other cycle routes) and some less so. Here are a brief description and a GPX file.
All_the_Royal_Parks_Snow_and_Blossom_