Nearby PAS finds — using public archaeology data on your DetectID map

The Portable Antiquities Scheme database is the largest open archaeological dataset in Europe — nearly 1.7 million finds, mostly reported by detectorists, mostly recorded since 1997. The Premium nearby PAS finds layer puts the slice of that database within 5km of each of your permissions directly on your DetectID map. Your private collection plus the public archaeological record, side by side.

How to toggle it on

Open app.detectid.co.uk/finds/map on a Premium account. In the layer-control panel at the top-right, tick Nearby PAS finds (5km). Purple dots appear within a 5km radius of every pin in your own collection. Tap a dot and a small info card opens.

What each PAS dot tells you

The info card surfaces what PAS publishes openly:

• Find type. Coin, brooch, buckle, mount, weapon-fragment, etc.
• Period. Roman, Early Medieval, Medieval, Post-medieval, Modern.
• Date range. The specific year window where known.
• Material. Silver, copper-alloy, lead, pewter.
• FLO district. The local Finds Liaison Officer area — not the parish, not the exact field.
• PAS record ID. A link out to the public record on finds.org.uk.

Why 5km

Five kilometres is a deliberate choice with three lines of reasoning behind it.

• Close enough to be informative.Most permissions sit in landscapes whose archaeological character extends a few kilometres in each direction. 5km is wide enough to capture the region’s period mix without drowning the map in dots from forty parishes away.
• Far enough to never compromise PAS privacy.PAS itself sometimes publishes at 1km precision for hoard or treasure findspots. Layering that data at the parish-FLO level over a 5km circle keeps detectorist-helpful while staying well clear of revealing anything PAS hasn’t already revealed.
• Caps the request size.Honest engineering reason: a 5km circle returns ~100–800 dots in active regions, which renders cleanly. A 50km circle would return tens of thousands in some places.

How PAS records relate to your own finds

Your private map is untouched by the PAS layer. Your pins are still your pins — only visible to you, at whatever precision you chose, never exported anywhere unless you explicitly share. The PAS layer is purely an overlay of public data on top.

When you turn it off, the PAS dots disappear and nothing about your collection has changed. When you turn it back on, the request to PAS is keyed off the centroid of your permissions cluster, not off your individual exact pins — so even the act of toggling the layer doesn’t leak your fine-grain location to the PAS API.

Use cases

Which permission for the weekend?

Suppose you have three permissions: a 30-acre arable in Norfolk, a 12-acre pasture in Suffolk, and an 80-acre ploughed field in Kent. Toggle the PAS layer and you can see at a glance which of the three sits in the densest archaeological region. Density isn’t a guarantee, but in a marginal weekend you’d weight toward the field where forty Romano-British brooches have already been reported in the 5km radius rather than the field where the records are mostly modern lead weights.

Spotting the period mix in a region

Filter the PAS layer by period (the layer panel has period chips: Roman / Early Medieval / Medieval / Post-medieval / Modern). Toggle Roman only and you see roughly where the Roman activity in your region clusters. Toggle Early Medieval and the pattern shifts entirely — Anglo-Saxon material concentrates around early-estate centres that don’t correlate with Roman density. Each toggle reveals a different landscape phase.

Cross-checking your own identifications

If the engine identifies your find as a Trumpet-derivative brooch, type IIB, ~AD 100–150, and you see eight similar records reported by other detectorists within your 5km circle, that’s social confirmation. If you see zero comparable records in the entire region, that’s a flag — not that the identification is wrong, but that you’ve found something unusual for the region, which might be worth pushing your FLO on.

Targeting site-types

A cluster of Roman pottery records within a 1km radius often indicates a villa or roadside settlement — not exactly on your permission, but close enough to suggest scatter. A cluster of Anglo-Saxon brooches in a region of otherwise quiet Roman finds often indicates a high-status early-medieval site nearby.

Caveats — PAS is imperfect

PAS data is brilliant and PAS data is also messy. Some of the biases worth knowing:

• Finder-reported. Everything in PAS got there because a detectorist (or occasionally a fieldwalker) reported it. Records reflect detector activity, not archaeological density. Areas with active local clubs report more; areas with hostile farmers or absentee landowners report less.
• FLO coverage varies wildly.Some FLO districts have full-time officers with strong outreach (Norfolk, Suffolk, Lincolnshire are excellent). Some are shared, under-resourced, and behind on data entry. The absence of records in a region doesn’t mean absence of finds — it might mean absence of recording capacity.
• Reporting bias by find type.Gold and silver get recorded. Worn copper-alloy coins often don’t. Lead weights almost never. The dataset over-represents metals that detectorists are proud of and under-represents the bulk-buckle, bulk-button, bulk-lead-shot side of the hobby.
• Backlogs.A find from your 2025 weekend might not appear in PAS until late 2026, depending on FLO workload. The layer reflects what’s been catalogued, not what’s been reported.
• Treasure cases differ. Treasure records have their own entry flow and can appear in PAS years late, or at coarser precision than ordinary records.

Why this layer is genuinely useful

Combined with the historic OS overlay and the Roman roads overlay, the PAS layer turns the map from a place to drop pins into a research tool. You can:

• Find a permission that sits on a 1888 deserted village footprint, 1.5km off Watling Street, in a 5km radius with 80+ PAS records weighted Roman and Medieval.
• Or a permission that sits in an apparently empty modern field, 4km from any road, in a 5km radius with twelve PAS records weighted Modern. That’s a permission to think about politely declining.

No single dataset reveals these patterns. Three layered together do.

And on the responsibility side

Seeing PAS dots near a permission isn’t a licence. It’s an aid to choosing where to ask permission and where to dedicate your weekend. Anything you find still needs reporting to your own FLO in turn — that’s how the dataset keeps growing. See Reporting your finds to PAS for the recording flow.

Next steps

• The historic OS overlay — layer one of three.
• The Roman roads overlay — layer two.
• Reporting to PAS — how you contribute back to the dataset you’re reading.