Why are the vineyards near Barcharach planted in vertical rows?

It may be related to sun exposure, where typical wisdom suggests planting rows in a North/South orientation so that vines get similar exposure on each side. But lots of factors can come into play, including the shape of the plot of land. As an example, longer rows require fewer (expensive) end poles.

I think you mean Bacharach. I've seen vineyards planted vertically in a few places. I guess its typically areas with very steep banks like Rhine, and more so Mosel and Douro. I would guess for a few reasons, one in terms of getting the best sun exposure and ease of tending for a couple. I'm pretty sure there were machines that went up the rows for picking in Mosel.

It's an unusual one. The majority of vineyards along the Rhine and Mosel are staked horizontally with verical paths in between, for safety reasons and ease of access, though I have seen a mix of horizontal and vertical rows (Black Cat, for example, near Zell).

It's primarily for picking. Vertical rows you can winch stuff up and down the row. Horizontal requires more human labor.

This interested me of course. I thought it was because Bacharach is on the left side of the Rhein and would not get as much sun as the right side, where the Rheingau is located, but it seems this was wrong. Found this snippet of info and it made sense to me. Having gone through the wine museum in Rüdesheim and looked at the old machinery at Kloster Eberbach, have seen a lot of those special harvesting tools they used to use on the vertical slopes.

The steepest vineyard slopes in all of Europe are found here. Some of the grape vines are planted in vertical rows while others are in horizontal rows. The grapes planted vertically are machine groomed vines while those planted horizontally are generally on the steepest slopes and are maintained totally by manual labour.

I have photos of the Black Cat vineyards near Zell. They are a mix of horizontal and vertical, sometimes side by side. On the steepest vineyard of all, Calmont on the Mosel between Bremm and Ediger-Eller, the vines are staked horizontally.

When visiting the area we say farm machinery anchored on roads at the top of rows and going up and down the steep slopes by winch line. Much safer for farmers.

Yes, I meant Bacharach, sorry for the extra R!

Thank you for all your thoughtful replies, I appreciate your insights!

As someone mentioned, it’s because pickers (and vine tenders) have to do the work and it’s much easier to climb straight than across a steep slope. Also the grapes are loaded into carts that can the. Be lowered to the botttom (or a terrace part way)