this is for gry/73 -- Hello again, as I recall I spent a lot of time tinkering with your itinerary, and never did see the final, but I hoped it helped. Now the EASY answer to the Nafplio beach question is -- did you click every link in http://www.visitnafplio.com as I ordered you to do?? If so, you'll have all the options; the choice depends on time, weather, etc. Here's another listing (which seems to be aimed at RV owners, but is good) - https://greeklandscapes.com/nafplio-beaches/ I can add my experience with each:
• TOWN BEACH - Arvanita... handy & lots of fun - you can see it when you're up in Acronafplia at the little park at the top of the "point" (great views!) you can walk down a ramped drive, or u can do the long sea-level walk around the Poin (MORE great v iews!) t... or drive to the parking lot. The "beach" because it's all rocks needs water-shoes (BTW highly advise u buy. $7 @CVS/walmart & pack instead of flip-flops - useful many beaches in Greece, AND Somehow not seen in shops there). Luckily there's a handy concrete platform (with sunbeds) u can get into water. The sea at Arvanitais like glass in AM, in afternoon begins swirly-whirly, like being massaged in a Bendix - startling but fun.
• "BANIERES" -- This is right on the sea-level path past the "point" ... former "Lido" swim club... not sand, just piers out into lovely deep water -- so handy for refreshing quick dip if u have hotel right in main part of Old Town .. also has a bar (!). As website notes, restaurant Agnanti is perfect for dining WITH sunset ... IF it's open (Covid has affected so many businesses)
• TOLO -- 15 mins outside of town, where many OId City tourists head ... sandy beach, nice descent but some drawbacks: this is a big "package holiday" w hotels jammed together & beach can be crowdy at center ... yet apparently NO public changing rooms or restroom facilities. For these u need to walk confidently into a hotel lobby acting as if u are a guest, & hope to spot a restroom - or else buy a soda at the outdoor bar, then ask for the facilities & carry your beverage thru lobby. Also, sunbed rental pricey for what you get.
• KARATHONA -- Haven't swum there, we got lost on its in/out roads... not that handy to Nafplio either.
• KASTRAKI BEACH at ANCIENT ASINE -- Now here's my little fave... First time, found it all by myself, took a bus & asked to be let off near Asine, walked 100 yards down a shady lane -- and there it was! A small cove, almost no one there in early June, tho u could look across the bay to jampacked Tolo. Somewhat rocky at water's edge (water shoes!) but crystal clear, great swims. Cove has ONE little taverna, family-run, with a WC to change in and 6 sunbeds & sunbrellas, free when u buy a beverage and why not? In fact, it's fun to stay on its canopied terrace for an early dinner at sunset. BTW, you should check out the Asine ruins... and beyond its walls, you walk a little road along a campground and !! a SANDY beach!! a couple of piers... NO facilities whatever... good for a dip if u have a car to change in & have brought drinks & snacks.