At the foot of the sport and trad routes behind the BNI boulder is the Everdry Wall and the Black Wall (more recently known as Old Man's Corner). It's not a bad place to warm up and there are some alright traverses here but if your climbing here it's more than likely that it's raining.
Even in very heavy rain it will offer some solace to the dedicated boulder but it does tend to suffer from seepage after a few days of constant rain.
Adding a circuit adds about a grade each time.