I’m fortunate; I have a university campus in my back yard. A block and half away, these days it is mostly empty, making for easy social-distancing while biking, walking, and inline skating. For 7 years now, I’ve been doing a local “hills route” that I conjured up, riding my single speed, hitting umpteen hills in about an hour’s ride around my neighborhood and campus. It’s a mesa, and so I drop down and climb back up, drop down, gut it back up, drop down … By the end of it, my legs are worked pretty well.
Make your own adventure, y’all!