 In 1674, the Italian diplomat Lorenzo Magalotti estimated that De la Gardie had at least 50 on-going projects in Sweden and its provinces, excluding the 37 churches he was constructing or repairing at the time.One of the churches De la Gardie restored was the abbey church of Varnhem, in which he established a family mausoleum where Magnus Gabriel himself, his wife Maria Eufrosyne, their son Gustav Adolf and daughter-in-law Elisabet Oxenstierna are buried.At Läckö, De la Gardie ordered considerable extensions, starting in 1654.