maybe not at this time of year (bit cold) but in the spring particularly i think it is the most delightful thing you can do . doing it alone is nice too. card games, junk food, music and good chats . bonus points if you have a go-to park.. it's the best
Your probably already have some of these on your list already, but:
▸ Go camping
▸ Rent a canoe/kayak if there's a body of water nearby with rentals available!
▸ Late night bonfire
▸ Picnic with friends
▸ Go to farmers markets/craft fairs
▸ Make art outside! (painting, drawing, writing, journaling, etc)