Location – Mullainagiri is located near Chikmagalur, (which is about 230 kms from Bangalore through Hassan.) The highest peak in Karnataka is on the Chikmagalur – Bababudangiri route, about 25 kms from the former. There is a road which goes most of the way to the top of the hill and this would be a good point to start the trek if the plan is to proceed till Bababudangiri. Otherwise, just a few hundred mtrs after the deviation to the left which takes you to the top by road (as proclaimed through a stone marking), there is a 'Sarpadari' to the peak which gets quite slippery during the rains thanx to some stones laid there.
Bangalore to Chikmagalur bus service of KSRTC is pretty good and you would want to take a bus at 11:30 or 11:45 to reach Chikmagalur at earthly hours. The first bus from Chikmagalur towards Kemmangundi is at 8 am. Alternately you can hire a jeep or an autorickshaw for about 100 bucks!!
The trek -
The trek up Sarpadari would take about 2 hrs to the temple at the top and is moderate to easy. Climb atop the hill and there is a route from the temple which goes till Bababudangiri. Routes to Bababudangiri - GaLikere - Kemmangundi are well documented and I can’t say much about this as we couldn’t even see the trail due to heavy mist enroute the trek up Mullainagiri. Caves near the peak are a must see ……………
Info I gathered but not first-hand –
Mulyangiri to Bababudan giri is downhill most of the way, around 15 km (some 7 km on tar road) which can be reduced by around 4 kms if the path next to the mosque is taken to climb up after Attigundi. The trek route takes about 1.5 hrs till you reach the road connecting Chikmagalur and Bababudangiri.
Babbudangiri to GaLikere is 4 kms on a tar road and GaLikere is supposedly extremely beautiful. J
Galikere to Maharaja's Bunglow Ruins [IB] is about 12-15 kms from where you can either trek to Santaveri (and view Kalhatti falls) or go to Kemmangundi. Either route is 6-7 kms on a jeep track.