GEO600 and KAGRA observe together https://www.mpg.de/18523825/geo600-and-kagra-observe-together
Right after the third observing run of the international gravitational-wave detector network ended in March 2020, the Japanese KAGRA and the German-British GEO600 detector made an extra lap. They continued simultaneously taking data for two weeks in a joint observing run. Results from the joint run were publishe in Progress of Theoretical and Experimental Physics.
.; Gras, S.; Grassia, P.; Gray, C.; Gray, R.; Greco, G.; Green, A.