Please Help Identify

Hello, I found this envelope in my inherited stamp collection. Please identify and provide information on history or value. I believe it has something to do with the Panama Canal Zone, maybe before Panama was Panama. Any information is greatly appreciated!!

Why Panama?
Bucaramanga and Puerto Wilches are two towns in Santander Department,Colombia

Not sure about Panama as Panama separated from Columbia in 1903. This one is postmarked 1928.

This particular envelope was with a collection of stamps and other envelopes from the Canal Zone, which is why I thought it may be related. I overlooked the date stamped on the back (rookie error). Please bare with me as I try to learn the ins and outs of stamp collecting. Does anyone else have any informtion about the stamps?

SCADTA - from what I read - This was the worlds 2nd airline, the first in the Americas. It operated from 1919 until WWII. After the war it combined with Colombian Air Service.
SCADTA Is Spanish for Sociedad Colombo Alemana des Transportes Aeroes.

Otherwise your cover was mailed and received in 1926 in Colombia. It is a nice air mail cover, except for the fold or crease, franked to the right with two air mail stamps issued in 1921. C25 - 5 Centavos and C26 - 10 Centavos The other two, not sure as I dont have my catalogue with me.

Edit: Scott #'s used above.

The stamps on the left are Michel # 291 ( from 1925) and Michel # 275 (from 1923)
I don't have Scott numbers