Kathmandu staff arrived at the Madras St store in central Christchurch this morning to find a smashed front entrance.
A drain cover had been thrown through the glass door.
Security responded at 7am, but the perpetrators were gone.
The store has had bollards installed to stop ram raids with cars, but these thieves got creative.
Kathmandu employee Jolann van Dyk said the robbery was "frustrating". He was unsure if anything had been stolen.
The footpath was littered with tags, which were collected as evidence by police, along with the drain cover.