A female Episyron rufipes [1,2,3], a spiderwasp.
Here she is digging a nest space in a small sand accumulation on the garden tiles that had been collected by the stacked wall behind it. The nest tunnel was not deep due to the tile blocking further development, which made her leave after some time.
In 2020 the species is present again, this time she seemed to be hunting on the bee hotel.

Literature
1 Nederlands Soortenregister2 Peeters, T.M.J., C. van Achterberg, W.R.B. Heitmans, W.F. Klein, V. Lefeber, A.J. van Loon, A.A. Mabelis, H. Nieuwen-huijsen, M. Reemer, J. de Rond, J. Smit, H.H.W. Velthuis, 2004. De wespen en mieren van Nederland (Hymenoptera: Aculeata). – Nederlandse Fauna 6. Nationaal Natuurhistorisch Museum Naturalis, Leiden, knnv Uitgeverij, Utrecht & European Invertebrate Survey – Nederland, Leiden.
3 Nieuwenhuijsen, H., 2008. De spinnendoders van Nederland (Hymenoptera: Pompilidae). Jeugdbondsuitgeverij.