Apart from his large baths at Rome, Caracalla, in my opinion, and as Favonius says did nothing with regards to a successful military campaign.

He abandoned the Caledonian campaign as soon as he took joint command with his brother Geta and he totally missed the perfect opportunity to finish off the Parthian Empire as a threat. The Alexandrian massacre has never been properly explained but somehow the young emperor was severely pissed off enough to unleash his men against unarmed civilians in the empire's second largest city.

He appears to have been a man driven to cruelty by guilt and insecurity, but was not without ability as a ruler nor concern for good government. He was patient and conscientious in the hearing of lawsuits. He also reformed the currency, introducing a new silver coin, the antoninianus. He also extended Roman citizenship to all non-slave males of the empire, although this was probably intended to increase imperial revenue and widen the obligation for public service

Like other sons trying to follow in the footsteps of a successful imperial father, Caracalla does not get any credit for his good points and receives a slating for his bad ones, which do far outweigh the good