Four nights split between Budapest and Lake Balaton turns a Vienna Marathon trip into a proper Central European loop, with the pace easing from city sightseeing to lakeside recovery as the days go on.
Getting There
The Railjet from Vienna to Budapest is one of the more satisfying short rail journeys in the region: flat Hungarian plain, the city appearing across the Danube, arrival at Keleti station in around two and a half hours.
Budapest: Days 1-2
The Hungarian Parliament building on the Pest bank is the most theatrical piece of architecture in the Danube basin, best approached from the Buda castle hill above the river or by boat from Vigadó tér. The Széchenyi thermal baths in City Park are the practical post-marathon asset: large outdoor pools at 38°C, manageable even on compromised legs, open every day of the week. The Great Market Hall on Vámház körút is a good, low-effort morning: two floors of Hungarian produce, paprika, Tokaji wine and langos stalls upstairs.
Lake Balaton: Days 3-4
Onward trains or a hire car reach Lake Balaton, Hungary's largest lake, in a couple of hours from Budapest. The lakeside towns favour walking and easy cycling over any serious exertion, a genuine gear-change from two days of city pavement. Very hot thermal pools, a feature of several towns around the lake, are worth approaching sensibly rather than lingering too long straight after a marathon week.
Getting Back
Trains run from lakeside towns back through Budapest to onward connections, or flights out of Budapest Ferenc Liszt International Airport work for travellers not returning via Vienna. April sits before the summer heat and before the full arrival of the river-cruise and lake-season crowds in both destinations.