Back in the day, it wasn't uncommon for movies to stay in theaters a long time. Especially considering Jurassic Park was the highest grossing film of all time at that point.
Here you can see it ran from 10 June, 1993 to 20 October, 1994:
boxofficemojo . com/release/rl2354939393/
Here you can see it ran from 10 June, 1993 to 20 October, 1994:
boxofficemojo . com/release/rl2354939393/