What is this list?

Every ROC (Royal Observer Corps) Bunker currently on record, shown as a searchable, sortable table with a companion map. Use the buttons above the table to switch between all bunkers, Master Posts only, and Group HQ bunkers only — on small screens these collapse into a single dropdown. The table shows a brief "Loading ROC bunkers…" message while the data fetches; if it cannot load at all, it will say so and ask you to refresh.

Row and marker colour key

Every marker on the map is a small coloured pin, so post type is visible at a glance without opening a popup — a dark pin for Group HQ, light blue for Master Post, and grey for a standard post.

Bonus column

Master Posts score +3, Group HQ bunkers score +5. Standard posts show no bonus. A bunker that qualifies as both a Group HQ and a Master Post is always counted as a Group HQ.

Table columns

Locator is the Maidenhead grid locator. Grid Ref is the OS National Grid reference (or Irish Grid for Northern Ireland references containing "GI-"). ROC HQ is the short code for the ROC Group area the bunker belongs to (e.g. BED, OXF, WIN). Nearest Postcode is for general location reference only, not a precise address.

Jumping to the map

Click any bunker Reference or Name in the table (both shown in blue) to open the ROC26 Map, zoomed and centred on that exact bunker with its popup already open. Clicking any marker directly on the map also re-centres the map on it.

Bunker popups

Each popup header is coloured by post type (see the colour key above) and shows the Reference. Coordinates are shown as a plain pair, e.g. 51.88734, 0.88295. A yellow bonus footer appears on Master Post and Group HQ popups only. Every popup — including non-ROC bunkers shown via the map's Non-ROC toggle — also has an Open in Waze button, which opens Waze and starts turn-by-turn directions to that bunker from your current location (Waze always uses live GPS as the starting point; there is no way to set a different starting point via this link).

The ROC26 Map

Markers are grouped into clusters when zoomed out — click a cluster to zoom in, or zoom further to see individual bunkers. Each bunker also shows a faint 1000m radius circle, shown in black on the street map and yellow on satellite view for contrast. The dropdown in the map header filters markers down to a single ROC HQ code; it stays in sync with the ROC Code dropdown above the table, so changing one updates the other.

Four buttons sit in the top-right of the map: Sat switches between the street map and Esri satellite imagery (the label changes to Map to switch back), Find Me (red) uses your browser's geolocation to drop a marker on your current position and centre the map there — your browser will ask permission first, and this only works on a secure (https) connection, showing a small banner if it fails for any reason — Non-ROC (off by default) reveals every other bunker the API returns that is not classed as a ROC Bunker, shown as pale yellow pins with a "NOT ROC BUNKER" popup footer, useful for double-checking nothing has been missed from the ROC list — and Group Areas (off by default, purple) draws the 25 ROC Group Area boundary polygons on the map, each with a popup showing its code and name.

The map only closes when you press the × button in its header — clicking outside it or pressing Escape will not close it, to avoid losing your place by accident.

Download KML

The purple Download KML button exports the complete ROC bunker list (never affected by the current search or filter) as a .kml file for Google Earth or similar mapping software, organised into folders by ROC HQ code. Pins use the same grey/light blue/dark blue colour scheme as Standard/Master/Group HQ posts, each with its own 1000m radius circle, and clicking a pin shows the same details as the in-app popup. KML icon shapes are limited by the format itself, so the pins look slightly different from the web map, but the colour meaning is the same. The file also includes a separate folder with the 25 ROC Group Area boundary polygons.

Searching and filtering

The Search box searches every column at once. The ROC Code dropdown above the table filters to an exact ROC HQ code. The three buttons (or the dropdown they collapse into on small screens) filter by post type.