In this paper, I argue that international environmental treaties can interact with other specialised areas of law applicable to the same subject matter in the same context by using the ‘reconciliatory approach’ (RA). This approach entails that the institutions established under the environmental treaties are empowered to develop the treaty provisions in a manner that may also take other legal areas into account and thereby be able to reconcile obligations of other specialised legal areas. The RA functions on the premise that international law is one system with the inherent ambition to coherently systematize its norms. By looking at the application of the World Heritage Convention (WHC) during the armed conflict in the Democratic Republic of the Congo (DRC), I will illustrate the relevance of this approach. In the case of the DRC, the WHC is applied in the same context as the law of armed conflict, also referred to as international humanitarian law (IHL). Because environmental treaties, counting WHC as one even though its scope of application also covers cultural heritage, consist of general principles and vague obligations, they often empower treaty bodies to develop the provisions into more detailed and substantive obligations. By adopting the RA, the decisions and recommendations adopted by the World Heritage Committee (Committee) – a treaty body established under the WHC – can to consider the rules of IHL as well as the UN Charter and the decisions by the Security Council. Such an approach allows the law-applying treaty body to reconcile different areas of law and thereby overcoming fragmentation of the international legal system. In the case of the DRC, on an informal basis, the Committee and the UN peacekeeping forces deployed in the DRC by the Security Council have agreed to perform operations that also protect the world heritage sites. This form of cooperation could be regarded as an expression of the RA to harmonise obligations set out in the different legal regimes applicable on the same subject matter. There is sound argument to apply the RA also beyond environmental treaties in the relations between other specialised legal areas for the purpose of creating consistency and unity in the international legal system.