No injuries were reported, but more than 1 000 homes in and around Simonstown have been evacuated, officials said.
"The City's fire and rescue services are still actively protecting property and lives throughout the City of Cape Town area, currently dealing with 11 fire incidents. The two major fires at the moment are the Somerset West and Simon's Town fires," said Cape Town Fire's Liezl Moodie.
While crews were still busy with damping down operations in Somerset West with helicopters assisting ground crews with flare-ups and hotspots, the city had to move quickly to send out more crews to Simon's Town where a fire was raging out of control.
Huge plumes of smoke were billowing over Simon's Town and surrounds, making visibility poor.
"Aerial support is still in operation assisting ground crews and firefighters by waterbombing in the inaccessible areas."
The City's Disaster Operations Centre was activated to coordinate the response to the fire.
According to Disaster Risk Management's Mandy Thomas, the South African National Defence Force, SA Police Service and metro police were deployed to the areas already evacuated.
"Metro Police, SPCA and Law Enforcement have assisted with the evacuation of domestic animals," said Thomas. Glencairn Express Way and Arsenal Roads were closed to traffic.
"Kommetjie road is congested and Traffic Services are on scene to assist with traffic flow."
Meanwhile, firefighters in the Rawsonville area, near Worcester, had to evacuate a resort at the foot of the Slanghoek mountains. The ER24 paramedic service said it had treated 22 people for smoke inhalation at the Slanghoek Valley resort.
"ER24 paramedics arrived on scene at the resort and found a number of people crowded around. Fire services were on the scene already battling the blaze on a number of the buildings."
"Ten patients were transported to Worcester Provincial hospital for further care. The remaining patients on scene declined transportation to hospital," ER24 said in a statement.