Last year's inaugural Hall & Oates-headlined Hoagie Nation festival turned out to be a big draw, and the Memorial Day weekend multi-act show at Festival Pier will return in 2018.

This year, the summer-starting gathering will take place on May 26, and, along with the storied Philadelphia pop-soul duo, co-headline status has been conferred on Train. The "Hey, Soul Sister" band fronted by Patrick Monahan has been a pop radio stalwart for going on 20 years.

Also on the not-yet-finalized bill: Fitz & the Tantrums, the well-matched pop-soul Los Angeles band led by Michael Fitzpatrick and Noelle Scaggs, 1980s local heroes Tommy Conwell & the Young Rumblers, and for those who get there early enough, free samples of hoagies from 20 Philadelphia-area delis.

>> Read more: Cold cuts and Hall & Oates made inaugural Hoagie Nation a hit

In addition, Sound of Philadelphia-centric band David Uosikkinen's In the Pocket will play, along with an as-yet-unannounced headliner at the Fillmore Philadelphia on  May 25, or, as it will be henceforth known, Hoagie Nation Eve.

Last year, Hoagie Nation took the Roots Picnic's place as the kickoff event of the summer concert season along the Delaware River.  The picnic traditionally happens a week later, on the first Saturday in June. Look for an announcement of that lineup in the coming weeks.

Hoagie Nation 2018 tickets go on sale 10 a.m.  Jan. 29 via Ticketmaster.