Battlegroup and TSTOS

Battlegroup is Ehasa’s multi-day international airsoft milsim event in Finland, previously known as TSTOS. For example, Battlegroup 2026 took place on 22–25 July 2026 at the Halli training area in Jämsä. This page brings together upcoming events and the archive of Battlegroup and TSTOS events.

From TSTOS Parola to Battlegroup

The first TSTOS event took place in Parola on 23 July 2016. Ehasa organisers had attended Berget events in Sweden and wanted to create something similar in Finland. TSTOS Parola attracted players from Finland and elsewhere in the Nordic countries.

In 2024, the event moved to the former Finnish Defence Forces training area at Halli in Jämsä. We also retired the Finnish TSTOS / Taisteluosasto name and adopted Battlegroup. The archive on this page therefore includes both names from the same event history. Read more about Ehasa’s history.

Find the right event for you

Read the event description before registering. Duration, factions, roles and practical arrangements can vary. Check the rules and participation conditions for the particular event: information from a previous year does not replace the current instructions.

If this will be your first event, start with our first-time player guide. It helps you identify the questions to answer before buying a ticket and planning your journey.

Registration and preparation

Choose an event from the lists below. Use the registration link published on its event page and read the separate event website if one is provided. Instructions for a particular event take precedence over this general introduction.

The Players service collects practical information shortly before and during an event, such as arrival details and a more detailed schedule. Check which services your event uses.

Explore previous events

Archived event pages contain descriptions and available photo links from earlier years. Photographs offer a sense of the atmosphere, but do not guarantee the content of a future event.

You can also explore Conquest events or browse all Ehasa events.

Upcoming events in this series

Upcoming events will appear here.

Past events in this series

22.–25.7.2026HalliBattlegroup

Halli

Battlegroup 2026

A four-day international milsim airsoft event held at the Halli training area in Jämsä on 22–25 July 2026.

23.–26.7.2025HalliBattlegroup

Halli

Battlegroup 2025

BATTLEGROUP 25 will be held on July 23 – 26, 2025 in a Halli training area in Finland. It is the biggest Milsim airsoft event in Finland with more than 650 players attending around the Europe.

25.–27.7.2024HalliBattlegroup

Halli

Battlegroup 2024

BATTLEGROUP 24 The event will be held on July 24-27, 2024 in a Halli training area in Finland. Game area The game area is Halli training area. The

24.–27.7.2024HalliBattlegroup

Halli

Battlegroup 2024

The event will be held on July 24-27, 2024 in a Halli training area in Finland. Battlegroup 2024 is a four days long milsim airsoft event THE EVENT TAKES PLACE AT THE OLD TRAINING AREA OF THE FINNISH DEFENSE FORCES CALLED “HALLI” IN THE CITY OF JÄMSÄ. THE AREA HAS EXCELLENT ROAD

3.–5.8.2023PadasjokiBattlegroup

Padasjoki

TSTOS 23

The event was held 2.-5.8.2023 in Finland in the areas of the Finnish defence forces, the municipality of Padasjoki and the city of Hämeenlinna. Combined, the event area offered a large and extensive road network. Also the combined area enabled the use of various vehicles such a

3.–7.8.2022JuupavaaraBattlegroup

Juupavaara

TSTOS 22

TSTOS 22 was held in Juupajoki in the old ski resort Juupavaara. The game area had plenty of altitude differences, interesting terrain, decent road network and some lakes. Originally, the event was supposed to be held in Finnish Lapland, but in the end the area was too expensive

12.–15.8.2021PadasjokiBattlegroup

Padasjoki

TSTOS 21

Battlegroup 2021 is a four days long airsoft eventThe event will be held in Padasjoki in the areas of the Finnish Defence Forces, the municipality of Padasjoki and the city of Hämeenlinna. Combined, the event are offers a large and extensive road network. Also the combined area e

11.–15.8.2021PadasjokiBattlegroup

Padasjoki

TSTOS 21: Company Wars

TSTOS 21 was organised in Padasjoki, mainly in the areas of the Finnish Defense Forces, Padasjoki municipality and Hämeenlinna municipality. Combined, the event area, due to its size and roads, enabled the use of versatile vehicles and waterways and, of course, even larger numbe

28.–30.8.2020PadasjokiBattlegroup

Padasjoki

TSTOS 20

Battlegroup 2020 was a three days long airsoft military simulation event. The event was held in Padasjoki in the areas of the Finnish defence forces, the municipality of Padasjoki and the city of Hämeenlinna. The event area offered a large fighting area and extensive road networ

15.–18.8.2019PadasjokiBattlegroup

Padasjoki

TSTOS 19

Battlegroup 2019 was a four days long airsoft event that combined milsim and larp elements. The event was be held in Padasjoki in the areas of the Finnish defence forces, the municipality of Padasjoki and the city of Hämeenlinna. Combined, the event area offered much larger size

19.–22.7.2018IlveskallioBattlegroup

Ilveskallio

TSTOS 18

Battlegroup 2018 was a 4 day long airsoft event combining milsim and larp elements. The event was be held at a Finnish Defence Forces Ilveskallio training grounds in Hattula, Finland. Because of the size and extensive road network of the area enables we could use various vehicle

20.–23.7.2017IlveskallioBattlegroup

Ilveskallio

TSTOS 17: The Code

Battlegroup 2017 was a weekend-long airsoft event combining milsim and larp elements. The event was be held at a Finnish Defence Forces training grounds in Parola. Because of the size and extensive road network the area enabled the use of various vehicles, both armored and wheel

23.–24.7.2016IlveskallioBattlegroup

Ilveskallio

TSTOS Parola

The first TSTOS event could be looked at as a big Conquest event but with much stricter faction-specific command structures and longer duration. The event truly offered strict faction structures and managed missions. The two main factions of the event were placed in their own ba