A couple of years ago I dug a bank into a south-facing slope near our house in order to attract nesting bees and wasps. It worked well and in sunny weather a number of species can be seen digging burrows. It has also attracted some of the cleptoparasitic bee species such as this Sphecodes ephippius I found re-filling a burrow she had raided.
This species lays her eggs in the nests of several other bees, in this case probably one of the many Halictus rubicundus nesting in the bank. Like this one I found at the entrance to her burrow on a cool morning.
Recently the spider-hunting wasps have become more active, such as this Priocnemis with a captured spider.