Eingang einer in den Hang gebauten Festungsanlage mit Schiessscharten und Panzersperren

BOTA — Bunkers On The Air

Radio operations from bunkers, barrier positions and fortresses — as part of a global programme.

The programme

WWBOTA (Worldwide Bunkers on the Air) combines amateur radio with military history — just as SOTA explores the mountains and POTA explores nature reserves. It is currently supported by 26 national programmes.

The Swiss programme, HBBOTA, was launched on 17 April 2026. Réduits, barrier positions and fortress artillery result in an unusually high concentration of sites within a small area in this country.

Which sites count

A bunker is defined as a structure built by the Swiss military, bearing an A-number, and whose location is publicly known — dating from the First or Second World War as well as the Cold War. Each site is assigned its own HBBOTA reference within the global scheme B/ + country code + four-digit number.

Activation

HBBOTA is not a competition: there are no rankings, no time pressure and no prescribed operating hours.

  • Valid activation: at least 25 QSOs on shortwave or mixed, at least 5 QSOs when operating exclusively on VHF/UHF/SHF.
  • The location may deviate by up to 1,000 metres from the specified coordinates.
  • Where zones overlap, up to five bunkers may be activated simultaneously.
  • Only direct radio contacts count — relay, satellite and network-based connections are excluded.
  • Each call sign counts once, regardless of the band.

Logs and Spots

Activations are uploaded as ADIF logs via the WWBOTA Logger; a WWBOTA account is required for this. The Ham2K PoLo app supports spotting and log synchronisation directly in the field. All sites are marked on the interactive WWBOTA map.

Awards

Activations and worked contacts count towards the WWBOTA diplomas, which are managed separately for activators and hunters — in addition to the lifetime diplomas, there are CW and DXCC rankings as well as activity weeks, which WWBOTA organises from time to time.

Getting involved

Anyone wishing to activate a site should check access arrangements in advance: many sites are on private land or are off-limits. The national coordinator for Switzerland is Johann Furrer, HB9HXX.

Image: WWBOTA (wwbota.net)