Most of the northern Grampians is currently closed after a bushfire ran through last year, and, Victoria Parks does not seem to be in too much of a hurry to open up the tracks or climbing areas, but, two hikes at the northern end - Mount Stapylton and Mount Zero are currently open. Both are short so you can easily do both in either an afternoon or morning.
Overlooking Stapylton Ampitheatre
Mount Stapylton is definitely the most interesting. The track runs up rock slabs to Flat Rock where there is a grand view of the impressive Taipan Wall, then descends a short distance to cross a burnt valley before climbing around the south side of Mount Stapylton and heading up to the summit on more rock slabs. A sign marks the end of the hiking track (marked by yellow triangles) but, if you are a peak bagger, you'll immediately notice that you aren't actually on top of Mount Stapylton which rises a short distance higher. Some old faded red arrows led out on rock slabs around the west side of the mountain and a few scrambling moves (some may not like this section) lead to the real summit. There is an impressive amount of rock all around and most climbers will be dreaming of wild new routes waiting first ascents.
On the other side of the road, Mount Zero takes less than an hour round trip along a similarly well marked track gaining a saddle on the east side and then romping up rock slabs to the top. A great view of Mount Stapylton awaits and a compass rose helps identify the surrounding features.