The Wellcome Collection in London, is a very easily accessible venue, opposite from Euston Train Station.
The conference spaces at the Wellcome Collection are in the lower floors of the venue, which is in itself a quirky museum/arts exhibition. Upon entry you head down one floor, either via the lift or stairs, to a very welcoming staff who will direct you to your space for the day. They will go through all of your needs for the day, delegate dietary requirements, they will also check in with you regularly throughout the day.
I often use the Burroughs Room on minus level 2, due to it being a very good stand alone conference room with its own catering. The room contains small art upon the walls, which helps bring through the rest of the venues feel, this makes what could be a very empty space into a warm exciting room.
The new catering options at the venue are great, with a personal favourite being the anti-pasti selection with buffalo mozzarella cheese.
The staff from the cleaners through to the venue manager are all very professional, polite and friendly. Over the few times I have been to the venue, I have built up a good rapport with different members of staff, due to their friendliness.
If you want a small conference or meeting space, easily accessible to delegates from all over, I would recommend the Wellcome Collection in London.