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The previous night was spent at Fersaid Bridge in the car park. In the morning the two bicycles were left behind and we went to Tulloch train Station by car. Left the car there, bought two SINGLE tickets and took the train at 8:13, arrived by 8:30 at Corrour, where this walk started from.
When off the train just follow the route to the Loch. When you've reached make sure you start heading up hill. The path ends up in a North-South direction route soon but don't worry, follow your compass to the direction of Carn Dearg. It may not be easy at the beginning but if you were looking for easy walks probably wouldn't have ended up here anyway

Between the two Munros there are no difficulties.
From Sgor Gaibhre descend NW. River can easily be crossed at a small dam, very close to the Loch.
A house with a sauna!!! is located on the NE tip of the Loch that is an excellent place to have a rest and some food. This is the point where the easy part of the walk ends.
Follow the road to the North part of Loch Ossian. Firstly you will need to be heading NW but the forest can't really be crossed just anywhere. There is a path where I crossed (see map) but pretty sure there were some fence to be jumped over as well. Anyway, once, out of the jungle turn West. The terrain was very wet and it's a tiring walk up to Beinn na Lap.
Descend NW and make sure you don't go far North as the river getting more rough. I could not find any point where it could be crossed easily but maybe I was unlucky. Once the other side of the river, climb up the hill, trying to aim the saddle between Garbh Beinn and Meall Garbh. This is VERY tiring.
Meall Garbh can be left out as we did on the way to Chno Dearg but I don't recommend to follow my route here. I would imagine the way through Meall Garbh is more rocky hence better to walk on.
The ridge between Chno Dearg and Stob Coire Sgriodain is really beautiful and comparing to the last few hours of torture it feels almost like walking on a motorway.
From the 5th Munro descend North and the road can be reached without difficulty.
We cycled the last ~5km from Fersaid Bridge to Tulloch train Station which was refreshing.
Good luck!