Registration for the 600k and 2x200k is open:
https://ner.bike/nersite/?p=4300
Please take note of the fact that registration for the 600k and the 2x200k lodging option closes AUGUST 26th. Yes, that's two weeks before the event - we have logistics to nail down before then.
Registration for the 2x200k without lodging closes on September 3rd.
Also, if you're interested in volunteering, let us know! Help on the Boston end for fast/straight-through 600k riders on Sunday morning is our biggest potential need, but we welcome any help.
Sarah & Tsun