20-May-2013 -- After visiting [42,-115], I headed eastward (crossing the Salmon Dam) to US-93, then headed back south into Nevada (passing through the casino border town of Jackpot, Nevada). I then took the "California Trail Byway" - a wide, smooth gravel road that meanders eastward towards the north-eastern corner of Nevada. I passed briefly through the far north-western corner of Utah, before crossing into Idaho and reaching latitude 42 North.
From here, I had originally planned to take U.S. Forest Service Road 1601, which runs westward, passing just north of the Confluence Point. I found, however, that this road - which appears to begin at a private ranch - was gated closed. So instead, I backtracked a little and took a turnoff at [41.99751,-113.98830]. This was 0.5 miles east of the point.
From here, I used a makeshift wooden 'bridge' to cross a small creek, then waded through a large marshy area (for 0.2 miles), before reaching a sagebrush-covered ridge. I then crossed a barbed-wire fence, before hiking the remaining 0.3 miles to the scenic confluence point.