Whether it’s the track of Manning Field, the trails of the Lynn Woods Reservation or the coast of Nahant, plenty of course options await North Shore runners this summer.This is a time for the reappearance of running staples like the Lynn Woods Summer Cross Country Races (in their 45th season) and the Nahant Triathlon (34th season). There are also new features to the season, including the inaugural adult and youth track sessions at Manning Field.On your mark, get set …Showing their popularity, the Lynn Woods Summer Cross Country Races drew an opening-night record of 230 finishers on May 28, and followed that up with 273 finishers on June 4.”We had a very big turnout the past two weeks,” said race director Bill Mullen, who noted that the weather has not been ideal weather-wise. “It’s a very successful start to the season.”I think people just enjoy running in the woods, somehow being able to get out in nature. Lynn Woods is just a great resource. People like the community and camaraderie.”There is no charge for the races, which include a short course, a long course and a junior high course (1.59 miles). Races begin at the Great Woods Road entrance to the woods on Wednesday evenings. The calendar even includes an extra-long course of 12-13 miles on June 18.Regardless of which race you choose to run, Mullen said, “you get a sense of the woods, whether it’s long or short. There are rocks and hills no matter which course you take.” Differences arise, though, on the “Tour de Lynn Woods” long races, when there are “not only longer distances,” Mullen said, “but significantly more single-track technical trails, more rocks and roots. It’s not easy to run at the same rhythm. You have to change your pace.”For the curious, the next “Tour de Lynn Woods” is June 25. The full schedule is online at lwrun.org.From the woods to the beach…The same week the Lynn Woods races began for the new season, the Nahant Triathlon opened (on Thursday, May 29) … although with the water still cold, there was no swim leg.”But they ran,” organizer Bob Levine said. “They biked. They had a good time.”The Thursday-night event was canceled last week, but at some point, the water will presumably warm up for triathletes.Levine said the event can draw 25 to 50 people, and 75 “when the weather is good.”The triathlon includes a 150-yard (450-foot) one-way swim in waist-high water; a 4.8-mile bike ride; and a 2.6-mile run.The only requirement for participants in the free event is a bike helmet.”Helmets are mandatory,” Levine said. “I don’t care what you wear swimming or biking. I would prefer not wearing locking cleats, as you couldn’t get your foot off the pedals.”Levine also does not allow earbuds.He noted there has been only one injury in the 34 years of the event, and said, “I don’t care who trains you, what I say goes. It’s all for safety. I’m on the Safety Committee at GE. Safety is No. 1.”The triathlon is held on Thursdays at 6:30 p.m. at Nahant Beach, beginning near the Tides parking lot.Levine said the season “could go a little longer. The beginning is lousy. It possibly could go longer. We’d have to start at 6 p.m.”Moving right along …For those runners looking for a beginning-of-the-week destination, how about the 400-meter track at Manning Field?The inaugural adult and youth summer track seasons, sponsored by Lynn Parks and Recreation, began last Monday and Tuesday (June 2-3).The first-ever adult race was a 10,000-meter (10K) event.”I think the folks who went had a good time,” said Mullen, who is also the adult track race director.He expressed some regret about turnout (seven runners) and said that “more senior runners, folks just learning how to run on the streets” might have “a little aversion to track, that it seems repetitive and boring.”However, the event did attract spectators who cheered on the runners as they completed 25 laps around the track.There is a 1-hour run on Monday, June 9, and a 2-person, 16K relay on Friday the 13th.”You hand off to yo