Four at Level 5: Arben Maliqi, Project Manager ESG + HR, Francesco Siciliano, GM a&o Venice Mestre, and assistant Alessia Doretto as well as Frank Hörl, GreenSign Sustainability Auditor (from left to right). This is the first time in Europe that a hostel has been GreenSign Level 5 certified. GreenSign is one of the most renowned sustainability certificates for the hotel industry — Photo by a&o Hostels
  • For the first time, a hostel in Europe has achieved the maximum GreenSign Level 5 standard
  • a&o Venice thus one of only 19 top-rated hostels in Europe
  • In addition: a&o Vienna Central Station and a&o Vienna Stadthalle achieve Level 4
  • a&o is the only hostel chain in Europe to report individual CO2 values

This has never happened before: the a&o Venice is the first hostel in Europe to achieve GreenSign level 5. Of the 800 or so hotels currently certified by the GreenSign Institute in Europe, only 19 achieve this maximum sustainability standard. General Manager Francesco Siciliano: "This is a tremendous recognition of our long-standing commitment to sustainable travel." Arben Maliqi, Project Manager ESG and HR at the Berlin based hostel chain, adds: "This certification sets the pace from now on - a&o Venice Mestre is our role model for all a&o locations."

GreenSign certifies that the a&o Venice Mestre has an "exemplary sustainability concept" with over 90 percent sustainability performance in core areas such as energy efficiency, water management, environmental management, procurement, quality management and sustainable development. Suzann Heinemann, founder and CEO of the GreenSign Institute, explains: "The extraordinarily good results of the a&o Venice in the GreenSign certification are an important sign for the industry and a milestone on the way to climate neutrality for Europe's largest hostel chain."

Founded in 2015, the GreenSign Institute certifies hotels in a "unique five-stage certification system" and not only examines the current status, but also "shows ways to continuously improve and further develop sustainability performance". To date, the Berlin-based company has certified around 800 hotels. Only three percent of them have achieved the highest level, quality level 5. GreenSign's sustainability certifications are among the most prestigious in Europe. In addition to the a&o Venice, the teams at the two Vienna locations, a&o Wien Stadthalle and a&o Wien Hauptbahnhof, are also delighted that their hotels have been upgraded to GreenSign Level 4.

"Growing sustainability spirit in the industry"

The hostel category is also thanks to the a&o Venice Mestre's entry into a top sustainability league. Sustainability, says Suzann Heinemann, is independent of the size or type of hotel: "We are pleased to see a growing sustainable spirit in the hotel industry and an increasing willingness for sustainability certifications. This positive development makes a significant contribution to climate protection and gives us hope."

Hardly any plastic, but food and art from the region

The GreenSign audit is comprehensive: management and communication, environment (energy, water, waste), biodiversity and cultural heritage, purchasing, regionality and transportation, quality control and sustainable development, social and economic responsibility are put to the test. Measures at the a&o Venice include

  • Avoiding plastic in the bar: 80 percent plastic-free bottles and glasses;
    - Use of food from local/regional producers;
    - Supporting local artisans and artists who exhibit and sell their work at the a&o, for example;

Recently, composters on the roof of the house have been recycling organic waste from breakfast/dinner. The plants in the hostel benefit from the nutrient-rich fertilizer produced in this way. Arben Maliqi: "Our goal is to be the first European hostel chain to be CO2-neutral in 2025. For us, net zero means reducing our own ecological footprint to a minimum and offsetting the rest." a&o is already the only hostel chain in Europe to show the individual CO2 value per booking on all reservations and guest invoices.

About a&o Hostels

a&o was founded in 2000 by Oliver Winter and currently operates 38 hostels with around 28,500 beds. The Berlin budget group is represented in 25 cities and 9 European countries. The next new location will be Florence from summer 2024. The a&o guest mix is diverse: backpackers are just as much a part of the a&o target group as solo travelers, families, school groups and clubs. The number of business travellers and senior citizens is also increasing. With 6.1 million overnight stays (2022: 5.55 million), 2.7 million guests (2.2 million) and a turnover of 217 million euros (172 million), a&o recorded its most successful year in the company's history to date in 2023. As part of its sustainability strategy, a&o will be net zero by 2025, i.e. CO2 emissions per overnight stay will then be less than three kilograms, which will be offset. More information at and overview of a&o locations at