Not too much of a drive for a day full of nature. A very good find is exploretrakaivilnius page that lists some great routes around Vilnius. "The most beautiful landscapes of Trakai" is what we went for. What we liked most about it is that it overcomes all the crowds leaving the best part actually to you. The route is worth its name. When we saw the Sinkhole of Strėva and the Devil's Pit, we felt like seeing something exceptional and probably wouldn't have ever found such a place on our own. I also advise using their directions and locations, as they are more accurate than just looking for directions on a map.