Coich Burn Broch
Looking at the map, I'm pretty sure this broch would have been in liine of sight of the Killin broch. It's hard to say, but if you draw a straight line between the two, the line of sight skirts the edge of Carrol Rock, and when you consider both brochs would have been between 20ft to 30ft in height, I would surmise that these two brochs could have had direct lines of communication. In any case, there is a cairn high on the hill behind Balnacoil lodge, which could have been a part of that communication chain.
Access is simple, and you can park 100yds down the single track road from the bridge. There is a gate in a deer fence beside the road, and from there an easy track takes you right to the broch, which isn't far up the hill.
Reproduced by permission of Ordnance Survey on behalf of HMSO. © Crown Copyright. All rights reserved.
Disclaimer: Some brochs were built with military defensive purpose, and as such can be situated in extremely dangerous areas, such as on the edge of cliffs and ravines. Additionally, these are Iron Age structures, most of them in ruins, and they are extremely hazardous, with crumbling stone walls and hidden chambers. Existing walls, lintels, and passages could collapse at any time. The information here is provided free but it is your responsibility to ensure its accuracy, ensure your own safety, and acquire permissions for access where necessary. Accessing brochs is done entirely at your own risk.