How do I write a tooltip for this list of cities?

distanceToSanFrancisco[s_] :=   QuantityMagnitude[   TravelDistance[cityList[[859]], Interpreter["City"][s]]] (* table1 takes a while to run on my system*) table1 = Table[{cityList[[k]],      distanceToSanFrancisco[cityList[[k]]]}, {k, Length[cityList]}]; citiesWithin[range_] :=   Module[{s = {}},    Do[If[table1[[k, 2]] <= range, s = Join[s, {cityList[[k]]}]], {k,      Length[cityList]}]; s] (*This lists all cities in California that are within `range` of San Francisco.*) radius = 25; tolerance = 0.05; a1 = GeoDisk[    QuantityMagnitude[     LatitudeLongitude[Interpreter["City"]["San Francisco"]]],    Quantity[radius, "Miles"]]; a3 =   Complement[    citiesWithin[radius*(1 + tolerance)],    citiesWithin[radius*(1 - tolerance)]    ]; Table[a3[[k]] -> distanceToSanFrancisco[a3[[k]]], {k, 1, Length[a3]}] Show[a2, GeoListPlot[a3, PlotMarkers -> Point], ImageSize -> Medium] 

This last one is what I want the tooltips on. For the red points around San Francisco, ideally I would like to get just city name. TIA