Simanggang (now Sri Aman) was a vital area point where the headhunters had to pass through to get to the trading ports of Kuching.

This 130-year-old Fort Alice overlooks Batang Lupar and was built to prevent the headhunters from passing down river to attack the coastal shipping trade.

This Fort was built to counter this threat. This is a bottleneck at Batang Lupar River and one of the outposts is located directly above this river bottleneck. The headhunters who traveled down with their longboats, were easy pickings for the British cannons, who managed to shoot most of them down from this Fort Alice vantage point.