The collapse of tourism caused by the COVID-19 pandemic is forcing many destinations to rethink their economic model, by focusing on sustainability and innovation. Advances in tourism impact assessment can not only improve tourism products and services, but also guide the sector towards responsible choices for the post-COVID era. The paper proposes a new way to assess tourism products using the Life Cycle Assessment—LCA methodology. Thanks to this method the authors quantify the environmental impacts of tourism choices and propose alternative green solutions. Innovation is therefore aimed at promoting a new awareness to support sustainable tourism after the COVID-19 pandemic. Once the impacts have been quantified, local governments can make decisions in their plans to promote the most sustainable solutions. The application of the methodology to a typical case study for the Mediterranean area—Cinque Terre National Park in the Liguria Region (Italy)—further helps administrations to transfer and replicate the authors’ proposal. The proposed methodology is applied taking into account several priority issues for host territories such as the activities carried out by tourists, tourism mobility, and accommodation.