Si monumentum requiris circumspice1
inscription on the grave of Christopher Wren, architect, in St. Paul’s cathedral, London
Not quite either of Salisbury’s real-world medieval cathedrals, but in reflection of them and of the massive cathedral projects across Christian medieval Europe2, the players can contribute to the construction of a great cathedral in Sarum.
This is represented with a rose window3 with nine4 rays which each can be claimed for a spot of Presence5 representing the memories and stories that family wishes to make indelible in the glass and stone of the construction, granting the ability to invoke the legend itself when it applies6.

How do you earn these?
I don’t know exactly (part of the general questions of downtime work), but each has six sectors around it. The “best” contributor each year among the families of the region can gain one of the sectors, and on the sixth year, one of them (presumably weighted to the family with the most sectors7) wins the ray as a whole. I think non-player families can win this, but the GM should take some consideration of the party of what memories that family want to have remembered, so it still feels like it builds into the same world, and either by steering or weighting the players should get a lot of these.
With six sectors in nine rays, and with cathedral construction starting in 508, it finishes right around the last year of the campaign in 560.89

Footnotes
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“If you would seek his monument, look around you.” ↩
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And especially the famous Gothic cathedrals, of which the later (real) Salisbury Cathedral is one. ↩
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It’s specifically a wheel window that’s a simplified version of Strasbourg Cathedral’s design. ↩
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Claimable. There’s more, theoretically, covered up by the other objects on the map design. ↩
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WIP the center cinquefoil also fits five floating ones… ↩
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For… a single point of Presence. It’s deliberately a little bit of a vanity project or a resource sink, with the main reward being putting your mark on the world and choosing the narratives that stick on the map itself. Like patronage in the real world. ↩
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I don’t want it to feel unfair or like a lottery, but I don’t want to just hand it to the highest bidder so that there’s a sense of trying to “catch up” even if someone’s already gotten several contributions in. ↩
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But not exactly - probably we kickstart it with a few freebie spaces for the initial contributions of getting it started. We could even give the first ray for initial groundbreaking, meaning it would complete in 556. ↩
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I could also see either letting certain years go un-filled or holding back further construction if a year is missed - to help the bitter years in the late campaign leave a mark. Having it only advance if someone contributes (enough) and making that costly for the years of the wastelands can make it feel like a challenge for the group to actually finish the cathedral in time (but there’s so little margin and so little room to catch up that it feels a bit unfair - lose a couple years and you’re done for). ↩