# Advanced concentric-circle import Official GBMaps guide for the classic map maker. VectorMaps has a different interface. Source: https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles Updated: 2026-09-30 Open Advanced import in Radial Circles to work in this overlay. Each row describes one centre and its distance rings. Start with the sample CSV, review the columns, then import when they are ready. The map stays in place behind the window. [Watch tutorial video](https://www.youtube.com/watch?v=W4-LXbJ53kI) Some videos show an earlier layout. The written instructions below describe the current controls; this is a guide, not a video transcript. ![Advanced concentric-circle import — current GBMaps controls](https://www.gbmaps.com/mcs/help/images/coverage-advanced-circles.png) Current controls. Select a numbered marker for its explanation. ## Distance rings on the map ![Three concentric circles over Yorkshire share one centre. Blue, green and rust-coloured rings are labelled 5 miles, 10 miles and 15 miles.](https://www.gbmaps.com/mcs/help/images/example-circles.png) A set of three rings with a 5-mile interval gives radii of 5, 10 and 15 miles from the same centre. The labels and line colours make the distances easy to distinguish. These are straight-line distances, so they are useful for a radius-based service area; use Distance/Time for a journey-based view. ## 1. Load a CSV file / Download sample CSV Choose a file in the supplied sample format. Loading fills the columns for review; it does not place circles yet. The CSV needs its heading row, including ring_id, ring_postcode, num_circles, ring_interval, ring_stroke_thick and ring_label_size, followed by the individual ring labels and colours. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--file) ## 2. Set ID and Postcodes Give each row a unique ID using letters, numbers, underscores or hyphens, plus a full UK postcode for its centre. An ID matching a set on the map updates that set. A new ID adds a set, and other set IDs are kept. Duplicate IDs within the import or a missing postcode stop it before any circles change. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--ids) ## 3. Circles and Interval Use a whole-number count from 1 to 20 and an interval from 1 to 100 miles. The outer radius is their product. Each row needs its own values; a single value does not automatically apply to every centre. On a small screen, scroll across the columns to reach the settings on the right. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--dimensions) ## 4. Line width and Label size Enter a whole-number line width from 1 to 5 and a label size from 1 to 10 for each set. These use the same ranges as the Radial Circles panel. Keep each row aligned with its postcode when pasting values from a spreadsheet. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--style) ## 5. Ring labels Enter a comma-separated list on each row, from the innermost to the outermost ring. Put a label containing a comma in double quotes, for example "North, depot",Outer ring. Blank labels are allowed. The CSV file uses separate ring_label_1, ring_label_2 and subsequent columns; loading converts them into the lists shown here. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--labels) ## 6. Ring colours Enter colours in the same inner-to-outer order. The existing importer supports red, blue, green, yellow and black. Supply a colour for each visible ring; a blank colour leaves that ring’s outline hidden. The sample CSV uses separate ring_colour_1, ring_colour_2 and subsequent columns. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--colours) ## 7. Import to map Checks the settings and locates every postcode before drawing any sets. Progress and errors appear below the columns. A failed lookup leaves the existing circles unchanged. After a successful import, matching IDs are updated, new IDs are added and the rings are shown. Close the window to inspect them; the normal Radial Circles controls can then edit them. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--place) ## 8. Clear columns Empties the draft fields and file selection. Circle sets already on the map remain. Use this when preparing another import; use Delete all circle sets from map only when you want to remove the artwork. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--clear) ## 9. Manage circle sets on this map Expand this section for Show / hide on map and Delete all circle sets from map. Hiding retains the sets for later; deletion removes all circle sets, including ones created outside this import. Neither action deletes independent dots or marker boxes. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--visibility) ## 10. Colour postcodes Colour postcodes uses all circle sets already placed on the map. There is no results list to copy first. On a coloured map, choose Add to existing to keep current assignments or Replace colouring to use only the circles. Unimported rows are not used. Undo reverses the colouring in one step. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--centres) ## 11. Download your circle data Downloads the current columns as circles-data.csv in a format this importer can load again, including IDs, labels and colours. This is the draft in the window, which may differ from the sets currently on the map. Keep the editable map saved as well if you need all its current settings. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--download) ## 12. Column guide, tutorial and closing the window Expand Column guide for the field rules or use Watch tutorial. Close, the cross, Escape or a click on the shaded background dismisses the overlay and keeps your draft. Closing during postcode lookup cancels that import and leaves existing sets intact. Once an import has completed, closing does not undo it. [Open this step](https://www.gbmaps.com/mcs/map-help.php?topic=advanced-circles#advanced-circles--close) ## Related guides - [Radial Circles: distance rings](https://www.gbmaps.com/mcs/map-help.php?topic=circles) - [Several circle centres & linked settings](https://www.gbmaps.com/mcs/map-help.php?topic=circle-sets) - [Colour postcodes inside circles](https://www.gbmaps.com/mcs/map-help.php?topic=circle-postcodes) - [Get a spreadsheet ready for import](https://www.gbmaps.com/mcs/map-help.php?topic=import-checklist) - [USA 5-digit ZIP maps: choose a state](https://www.gbmaps.com/mcs/map-help.php?topic=usa-zip-maps) - [Combine US states: ZIP or county maps](https://www.gbmaps.com/mcs/map-help.php?topic=usa-combine)