With 12 days between Monday night's trip to Wolverhampton Wanderers and United's next fixture, at home to Huddersfield Town, the Magpies will fly out to Alicante - just as they did last season, when they won three games in a row after returning to the UK.
The players will train twice a day before facing Russian side CSKA Moscow in a friendly on Saturday, 16th February at the 3,500-capacity Pinatar Arena near Murcia.
And Longstaff told nufc.co.uk: "To get away, to new surroundings, will do everyone the world of good. It'll give us the chance to get to know the new lads even better and spend a bit of time with them, so it'll be good for everyone.
"Obviously it's been a little bit cold here over the last month so it'll be good to get away to a new environment and get ready and refresh for the rest of the season."
CSKA Moscow, currently third in the Russian Premier League, played in the Champions League this season - they beat Real Madrid home and away, although failed to qualify for the knockout stages.
Last year, United rounded off their Spanish training camp with a 1-1 draw against Royal Antwerp and Longstaff said: "It'll be a chance to get all the lads some minutes, but it'll be tough - you see them on the telly playing in the Champions League and they've got some really good and well-known players.
"But it'll be a chance for everyone to get on the pitch and work on some stuff that we can hopefully use going forward in the Premier League, because obviously that is the main focus. But it'll be good to get away and refresh a little bit when we're out there and I think everyone's looking forward to it."
Before that, though, is Monday's game at Molineux. Wolves - who are currently in Marbella on their own training camp - sit seventh after a superb first season back in the top flight under Nuno Espírito Santo and Longstaff admitted: "They've got some really good players and they've been causing a lot of teams problems and scoring a lot of goals, but our staff will put a game plan in place and it's just about us going out and executing it.
"We'll be well-prepared for it but we know it'll be a really tough task against a good team who are in good form. They're pretty high up the table now so it will be tough, but all the games in the Premier League are tough and when you're scrapping for the points, like we are, you need to try and go to places like this and try to make sure it's a tough game, a horrible game, and see if we can get something out of it."
