As others have already said, this listing covers a large area, so choosing how to visit is a bit of a challenge.  I agree with the view that this would have been a stronger listing had a smaller number of sites, with a clear link to the criteria, been chosen, as per the other serial listings such as wooden churches etc.

In the end we chose the area around Lens as it seemed to offer a variety of different types of site which are included in the listing, such as the company town, old pit heads and workings, slag heaps etc. I will admit to being disappointed though, which is a shame as I generally enjoy industrial sites.

Initially we walked from the train station around the town itself looking at the various memorials, housing areas and company buildings included in the listing.  The walk was not that interesting though and at no time did I get a feel for Lens being a 'company town' which is what I had been expecting.  There was no cohesion between the sites we looked at, and due to the lack of information boards, no way of interpreting what we saw in the context of the 'mining town'.

After this we walked over to the Louvre Lens, something the town seems (rightly) very proud of.  The new building for the gallery is built on top of an old pit, and the surroundings here do include a few boards explaining the landscape around the museum.  Also near the gallery are some public buildings, eg church and school, remaining from the time of the mine and there is an information board here explaining their use and the company's influence on the community.  This part was more enjoyable.

Finally we visited the two slag heaps (or Terrils) next to Base 11/19, just to the north of Lens.  There is parking for this at Base 11/19 but no signs directing you to the heaps, in fact the paths from the parking over the footbridge to the base of the heaps is blocked in places.  However when you get over to the mounds, there is a board showing the walking routes around and up the heaps.  We chose the family route as we had had some very wet weather previously, and were very glad we did, the final ascent and subsequent descent was treacherous, with the provided steps having been broken and useless.  There are fabulous views from the top over the whole Lens area, giving a great impression of the impact mining has had on the area.

In addition we visited the Vimy Ridge Canadian Memorial, which is worth visiting in its own right of course, but also there are some impressive views of the mining landscape from here too.

So in summary, not my favourite industrial site, but it could be a whole lot better with some further investment and interpretative materials.