Finishing the Hardrock 100 once is difficult enough. Christopher Agbay and Jeff List have done it multiple times.

Agbay, of Jefferson, Mass., finished Hardrock for the second straight year late Saturday night, July 16. List, a resident of East Falmouth, Mass., finished in the early hours of Sunday morning, July 17, to notch an impressive sixth completion of what is considered to be the toughest 100-mile race in the United States.

The race began at 6 a.m. MST (8 a.m. EST) Friday morning, and runners had a 48-hour time limit to complete the course and kiss the rock that marks the finish line. The course includes more than 33,000 feet of vertical gain high in the mountains around Silverton, Colo.

Kilian Jornet, 28, of Spain, and Jason Schlarb, 38, of Durango, Colo., tied for the victory in 22:58:28, notching the second-fastest time ever while running the course clockwise. Jornet set the record of 22:41:33 at the 2014 race – his first of three straight victories.

Although neither Agbay nor List were in the hunt for the win, both battled through the difficult course and were among the 114 runners to finish the race out of 152 who started.

Agbay put together a strong, steady performance. Other than a 44-minute rest at mile 51.8 in the early hours of Saturday morning and a 23-minute break at mile 58.3, he didn’t linger long at the aid stations and kept moving forward efficiently. He kissed the rock at 9:56 p.m. Saturday, completing the course in 39:56:43, good for 51^st place overall. In 2015, he finished 64^th in 39:46:52.

List successfully navigated the Hardrock course for the sixth time, but it also was his longest journey on the rugged course. His fastest time came during his Hardrock debut in 2009 when he finished in 38:54:43. This year, the clock read 43:57:59 when he kissed the rock a few minutes before 2 a.m. in 82^nd place.

List finished the 2011 race in 40:57:00; the 2013 race in 39:51:11; the 2014 race in 40:17:43; and the 2015 race in 42:35:49.