Honister Pass climbs to 1,167 feet on the B5289 - one of three road passes linking the Keswick and Borrowdale area to the lakes of Buttermere, Crummock Water, and Loweswater. The other two are Whinlatter Pass to the north and Newlands Pass between them. Honister is the southernmost, the highest, and the steepest of the trio, with gradients up to one-in-four (25%) on the climb out of Borrowdale. The saddle at the watershed is called Honister Hause, using the Cumbrian word hause for such a feature, and from the top you can drop in either direction: north-west down toward Buttermere village and Gatesgarth at the southern end of Buttermere lake, or south-east down to Seatoller in the valley of Borrowdale.

Most mountain passes empty out at their summit. Honister does not. At the top of the pass stand Honister Slate Mine - the last working slate mine in England - and the Honister Hause Youth Hostel, where coast-to-coast walkers and climbers stop for the night. The two buildings exist because of the same geology: the green slate beneath them has been quarried here since the late 17th century, and the road across the pass exists in part to move that slate out. The mine still runs underground tours of the workings and operates England's first via ferrata, where harnesses and fixed cables let visitors climb cliff paths that miners once worked. From the summit, footpaths lead west to Fleetwith Pike, south to Grey Knotts, and north to Dale Head - turning the pass into a hub for some of the most accessible high-fell walking in the Lake District.

Storm Desmond pushed Atlantic moisture against the Lake District fells for almost two days in early December 2015. The mechanism is well understood: warm, wet air rising rapidly over the western escarpment cools and dumps its water on the windward slopes. Honister Pass sits squarely in that target zone. By the time the 24-hour total reached 341.4 millimetres, every river downstream was in flood. Cockermouth went under for the second time in six years. Carlisle's Eden burst its banks. The Honister rainfall figure became the new official UK record, and it remains so. Drive the pass in any heavy rain since and you can see the system at work - water sheeting off Fleetwith Pike, becks rising visibly in minutes, the road glassy with runoff.

The B5289 is a public road, but it is not an easy one. The Borrowdale side rises steeply through tight bends past slate spoil and bracken. The Buttermere side drops just as steeply, with views down toward Gatesgarth and the lake opening below. In summer the road is busy with cyclists and walkers, in winter it sometimes closes for ice and snow, and at any season the weather can change within minutes. The pass is not the most scenic in the Lakes - that competition is crowded - but few crossings tie weather, geology, and human work so tightly together. Slate beneath. Rain above. A road running between. Everything you see has been shaped by one or the other, or by both.