Let's get the bad out of the way first - even if you book and pay for your tour in advance, you still have to pay $10 parking fee. They only accept cash. The woman on the parking lot entrance is extremely rude, and will make your drive 4 miles north to an ATM even if this means missing the tour you booked. Her advice was "Well you shouldn't come to a State Park without cash". No warning of this on booking email for us non-Americans who don't know about State Parks. She did, however, (at my request) book us onto a later tour.
This is really sad, because it gives a really bad first impression of the most amazing place. EVERY other staff member, and the volunteer docents who led the tours were so polite, friendly and well informed. The actual walk experience was amazing - we have seen elephant seals at various points on the coast, but to get to the viewing platform at Ano Nuevo you walk through the sand dunes - where there are frequently seals just lying around. You have to be careful because "Seals have right of way" :) and you need to get out of the way if one is coming your way fast. But what an incredible way to see them up close. Particularly the "weaners" who are the pups old enough to be left to fend for themselves come off the beach to the dunes a lot because its safer to not be around the males while they are fighting for mating rights. It was a totally magical experience - in fact we couldn't use half the viewing platform because there was a huge male elephant seal just sunbathing up there! We've seen them at various points (including Point Reyes) and this is the place and the way to see them - you will never get a better view! Take water because it is a longish walk to the dunes, but an easy one. Reserve early if you want to go on a weekend - those tours book up fast. It's a MUST for anyone on the coast Dec-Mar - but remember to take cash.
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