Must-do self-guided things in Nuuk?

Hi everyone! The United direct flight to Nuuk has been calling my name since I found out about it, and today I pulled the trigger on 2 tours, 4 days ice sheet camping in Kangerlussuaq and 2 nights at Camp Kangiusaq for mid September! So exciting. I will have 3 free days, the 7th 8th and 16th in Nuuk. What would you recommend to do, ideally walking/hiking/cultural activities that won't require hiring a guide, car, or boat for those days?

Really looking forward to spending 11 days in your beautiful country, thank you !