The traverse under Easegill between Lancaster Hole and Link Pot is an excellent trip, and well worth doing, whether you start from Top Sink and finish at Bye George, or start at Lancaster and finish at Link Pot. This guide is mainly concerned with describing the route under the gill, and so goes for the shorter option.
When planning the through trip, it is advisable to become familiar with the way through the Earby Series first, where time can be lost between Stake Pot and the pitch into the lower series. A trip to Cape Kennedy is a good opportunity to gain familiarity with the route, as well as being a worthwhile trip in its own right.
Note: the passages below Maple Leaf pitch flood to the roof, and this route should only be attempted in dry, stable conditions.
Coming from the Stop Pot direction, the entrance to the Earby Series is on the left hand side of the passage a few metres before the start of the descent to the Stake Pot col. Coming from Stake Pot, it is the first passage on the right after the climb up from the col.
It begins as a reasonably-sized arch-shaped passage which after surmounting some boulders, turns back to the right and becomes smaller. The passage then traverses some small drops which are associated with the Stake Pot Inlet series. Make sure you stay up. There is then a half metre step down into another passage, close to a T-Junction with a rift passage going off to the right. Keep straight on, and clamber over or under a wedged boulder to enter a thin stream passage near the roof. Follow this joint passage through a series of minor acrobatic exercises. After a hundred metres, the stream enters from the left. Carry straight on, and after a further few metres duck under the right hand wall into a crawl which soon leads to an aven with an in-situ iron ladder. This is Cunuck Aven, and the start of the Earby Series proper, which is off to the right as you step off the ladder.
The first section of the Earby series follows a large, mainly sediment-filled, phreatic passage, with a succession of crawls linking larger chambers. Although the way through is not always immediately obvious, it is not possible to go far wrong. At one point, there is a decorated low chamber on the left, and the way is through there. Eventually, there is a descending, narrow rift by the right hand wall, with a continuation alongside it up over some boulders. Either way will do, but the latter is easier, and leads to a climb down into a larger chamber. The descent looks disconcerting at first, but traversing along the ledge leads to an easy, lightly-watered, scramble down a concealed crack.
The slope at the far side ascends into Brew Chamber, and from here a low crawl descends to the left. This leads into a flat-out downwards slither to the top of a slope over-looking Long Gallery. To the right, the passage chokes, but a way can be found between some boulders down to the top of a rift with the sound of a stream below. Traverse along a broad ledge until it is possible to cross over to the far wall, where a rope climb descends to a lower level. Below this is the continuation of the traverse until a 3 m descent can be be made into an obvious pit - Rat Pit Chamber. The passage then passes under a gothic arch draped with stalagmitic curtains, to the start of a traverse. Another couple of metres reaches a rope which is the top of the descent into the lower series. From the main High Level Route to the top of the pitch takes about half an hour.
The pitch drops down a pleasant shaft, and a short section of low passage leads to a junction with an inlet. Continuing downstream the passage morphs into a sauntering mud-strewn canyon passage before becoming lower again. Turn left up the next inlet (if you encounter a sump, you've gone too far) and past an attractive inlet on the right. The way past here is marked by a scramble into a muddy bypass, and a couple of passages to the left which should be ignored. Twenty minutes after leaving the 88ft pitch, you will arrive at the imposing Echo Aven.
Once you have successfully overcome the exit to the pitch and the short climb above, you are just ten minutes away from the Link Pot entrance. Follow the canyon passage upstream for a minute or so, until an inlet passage enters from the right, and a large chockstone boulder forms a barrier in the passage ahead. Over the chockstone, the passage steps up a little, and a a smaller passage comes in from the right. Squirm up into this, crawl under a large boulder, and a gap will be seen in the boulders to the left. Wriggle through the only possible route for a few metres until you exit at a short ascent onto a bedding roof above a tight canyon. Follow the bedding across the canyon, and you'll soon emerge into Hilton Hall.
After 50 m of easy walking, a boulder pile appears in the passage ahead. To the left, is an alcove where you find the bottom of the entrance pitch (and where the difficulties start!).
This is an excellent trip which traverses a wide variety of passages. It is, however, quite tiring and not suitable for novices.