Hi, Here is a Bee House, some bees (as the Osmia cornuta) need to find holds (in trees,houses,etc) to keep their babies safe, this kind of bees doesn't produce honey but they help a lot to pollinate the fruit trees, so with this bee house you can help them, keep the bee house over 50 cm of the ground with the N-E to S orientation (morning sun) ...

https://wildbieneundpartner.ch/ https://en.wikipedia.org/wiki/Osmia_cornuta