As a two country event we have two of most things, including registration sites. If you are a Canadian or permanent resident of Canada you should register on the Canada site. If you are a citizen or permanent resident of the USA you should register on the USA site. Runners from other countries may register on either site.
If you are from neither Canada nor the USA you may register on either site.
NOTE: Registration for the cross-border races (marathon, half marathon, ultramarathon) closes at midnight on 31 May to allow for border security clearances. 10K runners may continue to register online through 6:00am on Sunday 27 June (Race Day) or in person at the Lubec School from 2:00pm Friday 25 June through 7:45am Sunday 27 June (Race Day).