Aarhus is surrounded by beautiful beech forests; take a walk in Marselisborgskoven or in the deer park.
As a coastal city, there are many beaches to walk - just remember warm clothes October through early April. There are history trails from Moesgaard Museum right down to the water, with reconstructed stone age, iron age and viking houses and tombs, rune stones etc.
The local soccer team AGF, plays their home games at Atletion (http://www.atletion.com/), which can hold around 21.000 in attendance. If you're a soccer fan, don't miss a home game Played on Saturdays or Sundays as the atmosphere is amazing during game night!