The phrase "amassed in front of" is correct and usable in written English.
It can be used to describe a gathering or accumulation of people or objects in a specific location, typically in a visible or prominent position.
Example: "A large crowd was amassed in front of the concert hall, eagerly waiting for the doors to open."
Alternatives: "gathered in front of" or "assembled in front of".
A chanting crowd of about 30 people stood behind him and perhaps 100 amassed in front of him.
By noon, hundreds of students, some waving American flags, had amassed in front of Low Library, the administrative center of the campus, for a program organized by students representing all political views, including pro-Israel groups, gay and lesbian rights groups, Iranian student organizations, the Bahai Club and the college Republicans and Democrats.
The trend continued in the AIDS quilt, with its handmade images and mementos, and reached a peak of public participation with the oceanic expanses of flowers amassed in front of St. James's Palace after the death of Diana, Princess of Wales.
As soon as the Poles left their ramparts, the sortie came under fire of Russian artillery amassed in front of forts 54, 55 and 56.
McClellan was thus required to give chase without any benefit of the heavy artillery so carefully amassed in front of Yorktown.
As throngs of activists both for and against gay marriage amassed in front of the courthouse, the only thing most everyone seemed to agree on is that the politics of this issue have moved extraordinarily fast.
In Pakistan, thousands will amass in front of the U.S. consulate in Karachi with bricks and slogans against violence between Israel and Hamas, but not the almost weekly Al-Qaeda assaults inside their own borders.
But soon crowds amassed, standing in front of her section of table, with just one thing in mind: Gwyneth.
Living in shit was evidently no problem for them, since they did nothing about the rubbish amassed, shin-high, in front of their door.
Leaving Victor Verster on 11 February, Mandela held Winnie's hand in front of amassed crowds and press; the event was broadcast live across the world.
Teams can only beat what is put in front of them, but United amassed a greater proportion of the total points available than their Spanish rivals to finish top.
