Cutting the ribbon was singer/songwriter Alison Moyet, who was moved to support the charity after her mother passed away with dementia last year.
But for the star it was not enough just to show her support by attending. She also created a JustGiving page
in the run-up to the walk, raising over £6,000!
"Dementia has blighted my family and so it"s really salient to me to support Alzheimer's Society," Alison said.
"Memory Walk is an opportunity for everyone to come together to show solidarity in their commitment to beat dementia.
"It's been such an uplifting day in the face of a condition so devastating," she continued.
"Fundraising events like Memory Walk are so important to continue to fund research to find a cure and help future generations."
The walk was the biggest that Sussex has ever hosted, with four-times the number of walkers compared to last year. Money raised from the event currently stands at £90,000 – with donations still coming in!
Also taking part in the walk was Charlotte Wood, 29, from Brighton, accompanied by four other family members, ranging in age from 24 to 65.
"It feels special to be part of such a successful Memory Walk because it"s so close to our hearts.
"We are walking for my nan, Molly Stevens, who passed away in April this year,"
Charlotte explained. "She was such a bright, caring person with the warmest smile and biggest heart. She would be so proud of us, knowing we are doing this for an amazing cause. She was such a giving and caring lady"
Molly lived with dementia for 10 years following her diagnosis and was lovingly cared for at home by Charlotte and her family.
"Nan was diagnosed with Alzheimer's disease in 2005," she explained.
"It was shortly after Grandad passed away. We believe it was linked to her heartbreak, because they were the most in love, beautiful couple. She was devastated by losing him."
"Alzheimer's didn't define her," Charlotte continued.
"Despite her disease, Nan fought hard and was still smiling and laughing, like she always did, until the end."
"As a family we've received so much support from Alzheimer's Society," said Charlotte.
"It is so important to unite together to fight dementia. We must keep fighting to support future families."
Over 24,000 people across Sussex are living with dementia, with almost 10% of these based in Brighton and Hove.
Jess Goodwin, Memory Walk Officer for Sussex, said:
"Brighton Memory Walk has been such an inspiring day! People of all ages and abilities stepped out together with a shared commitment to help people affected by dementia in our community.
"For every 1.5 people in Brighton and Hove with dementia, there was one person walking here today. That is an incredible ratio.
"We have already raised £90,000 from the event, with donations still coming in! Every person, every pound, every step will bring us closer to a world without dementia."
From the money raised, £650 would pay for a brain scan to help diagnosis, £100 would allow someone with dementia to attend ten Singing for the Brain sessions, £20 would cover a month"s attendance at an Alzheimer's Society's Dementia Café.
To find out more about Memory Walk visit www.memorywalk.org.uk and sign up today to walk for a world without dementia.