How to print a city map in large format: A1, A0 and tiling onto A4

You need to print a city map in large format: an A1 poster for the wall, an A0 sheet for the project room, or a city map "on A4 sheets, in parts" to glue together at home. Both cases are solved the same way: take the map as a vector PDF, set the scale and margins, then either hand the file to a print shop or tile it onto A4 sheets in Acrobat. Let's go step by step.

Why printing a screenshot large is pointless

A browser screenshot is a raster of roughly 1920×1080 pixels. On paper at the print standard of 300 dots per inch it honestly covers about 16×9 cm — half an A5. Stretched to A1, it becomes roughly 60 dots per inch: street labels turn to mush, thin road lines turn into staircases.

A vector file (PDF, SVG) works differently: it stores the lines and outlines themselves, not pixels. The very same file prints equally sharp on A4 and on a 3×6 m banner. A detailed breakdown of the difference is in vector vs raster maps.

Which file to use for large format

• PDF — the universal choice for a print shop: vector, embedded fonts, opens everywhere. This is what you'll be asked for nine times out of ten.
• SVG — if the map needs work before printing: recolouring, a title, a frame, a logo. Save to PDF after the edits.
• PNG — only if you're printing raster deliberately. Then count the pixels in advance: A1 (594×841 mm) at 300 DPI is 7016×9933 pixels, A0 (841×1189 mm) is 9933×14043 pixels — hundreds of megabytes.

For posters viewed from one or two metres, 150 DPI is usually enough; for a map people walk up to and read side-street names on, use 300 DPI.

One detail of the builder: for a plotter pick the "PDF vector" tile. The tile labelled simply "PDF" gives a raster PDF (sheet up to A2, 300 dpi) — fine for viewing and sign-off, but not for printing A0.

Scale: "1 cm equals N metres"

The scale denominator takes one calculation: ground width divided by paper width in the same units.

Example: a district 5 km wide printed along the long side of A1 (841 mm). 5,000,000 mm / 841 mm ≈ 5945, rounded to 1:6000 — meaning 1 cm on the map is 60 metres.

The reverse is useful too: if you need 1:2000 (1 cm = 20 m), that same A1 side fits a strip of 841 × 2000 = 1,682,000 mm, about 1.7 km. Pick the export area for the scale you need up front instead of stretching things afterwards.

Margins, bleed and the safe zone

1. Bleed — 3-5 mm on each side if the map is printed edge-to-edge with no white border. The map background must run past the trim line.
2. Safe zone — 5-10 mm inwards from the trim line. Keep everything important (legend, caption, city name) inside it: the cutter wanders by a couple of millimetres.
3. Printer hardware margins — 4-5 mm around the edge on an office laser printer, so true edge-to-edge printing on it is impossible.

What to check with the print shop

Before sending the file, ask three things: do they need CMYK and which colour profile, do they want bleed and crop marks, do they accept a plain PDF or require PDF/X. Wide-format plotter printing (rolls of 610, 914, 1067 mm — A0 fits comfortably on 914) usually takes an RGB PDF without complaint; offset almost always asks for CMYK. Colour and profile details are covered in preparing maps for print.

Tiling the map onto A4 at home

If there's no plotter around, a PDF prints as tiles on an ordinary printer:

1. Open the PDF in Adobe Acrobat Reader.
2. File → Print, in the "Page Sizing & Handling" block choose Poster.
3. Tile Scale — 100%, otherwise the map scale drifts.
4. Overlap — 5-10 mm: that strip is what you align the sheets by when gluing.
5. Enable Cut Marks and Labels — they make assembly three times faster.

By area, A0 is exactly 16 A4 sheets and A1 is 8; in practice printer margins and overlap push that up by a few sheets. Gluing works best with an overlap, trimming only one edge of each sheet along the mark.

Easier — get a ready file straight away

There's nothing to trace or stretch: select the piece of the city you need and download it straight as PDF — vector, with labels and layers, ready both for a plotter and for A4 tiling. If a designer will work on the map, take SVG; for fixed-size raster printing, PNG. It's free and takes seconds, and the specifics of PDF export are in the PDF map guide.

In short

• A screenshot on A1 gives about 60 DPI — only vector prints large: PDF or SVG.
• Scale: ground width in mm / paper width in mm. 5 km on A1 ≈ 1:6000, i.e. 1 cm = 60 m.
• Bleed 3-5 mm, safe zone 5-10 mm inwards from the trim.
• A4 tiling: Acrobat Reader → Print → Poster, tile scale 100%, overlap 5-10 mm.
• A0 = 16 A4 sheets by area, A1 = 8 sheets; in practice margins and overlap add a few more.