The Büchenbronn observation tower with its height of almost 25 meters offers a really good view. Up to the top there are 125 steps, so this is feasible without major exhaustion. There are also some benches partly with tables that invite you to rest.
The ride with a bike to the highest point of Pforzheim is worthwhile but is very steep along the advertised (hiking) path. By bike it goes over stick and stone ... a very nice and steep (e) Moutainbike Trail!