The Welsh FA confirmed the Canaries pair in the 20-man squad on Tuesday morning ahead of the tournament, which gets underway in North Wales later this month.
It marks the nation’s fourth appearance at a men’s intermediate age-group finals.
Drawn in Group A, Cymru will face nine-time EURO champions Spain, former winners Germany and Denmark.
Scheduled to arrive in camp on June 23, Myles and Lines will begin preparations for the opener against Spain on June 28 (6pm) at Wrexham’s Racecourse Ground before facing Germany on July 1 (8pm) and Denmark on July 4 (2pm) at the same venue.
Goalkeeper Lines, who joined Norwich from Coventry last summer, has been capped six times at Under-19 level for the Dragons, while City teammate Myles has made ten appearances and scored twice.
Former defender Gunter is relishing the challenge of leading Wales’ next generation through a landmark home tournament.
“Personally, I cannot wait for the tournament to start and see the players perform in a major finals,” said the Wales MU19 head coach.
“From my own experience and knowing what tournament football can give you as an international player, I’m extremely proud to lead these boys and staff into this summer and show all the positive work being done.
“Hosting a EURO finals is an amazing opportunity for our young players to show the very best of Welsh football on the biggest stage, and playing at home in front of our supporters is something they will never forget.”
