Referring to the sound of an extreme megaphone:
地上なら、何十キロと遠くまで達する音だ。
If it's above ground it is a sound that will reach as far as several tens of kilometres.
I'm pretty confident I've translated this correctly but I don't understand how the と particle is working here.
My guess is that it is being used to mark a standard for comparison. So in really bad English I have "The sound reaches distantly, as much as compared to tens of kilometres".
If my above assumption is true then what happens if I remove まで? My guess is that the sentence becomes ungrammatical. So I can have 地上なら、遠く達する音だ. But neither 地上なら、遠くまで達する音だ nor 地上なら、何十キロと遠く達する音だ make sense on their own.
In summary I feel that the と and まで particles are teaming up in this sentence. To give AとBまで with a meaning "As much as characteristic B when compared to A".
Could I rephrase it as:
地上なら、何十キロほど遠く達する音だ。
Would that be wrong? Have a different feel?
Is my analysis correct? If not please enlighten me.
Edit:
The suggested duplicate explains と. but it leaves me more confused, because I thought まで was playing the part of 'as much as'. What is まで doing? Can it be removed? I still don't understand the overall grammar of the sentence.