Czechia

Bollards: orange double reflectors front / single white back (rare blue/red variants)

Slovakia: Czech letters Ř Ě Ů vs Slovak Ľ Ô Ä; sign borders separated from the edge → Czechia.

Extra-wide B-type guardrails - only CZ+SK in Europe (SK occasionally uses others; CZ consistent)

Slovakia: Language letters decide.

Wide round concrete poles, often in pairs; poletops w/ short metal bars; upside-down-triangle supports (also DE/AL/RS/RO); upward-angled trident tops = CZ+SK only; lamp posts w/ thick bolted base

Slovakia: Street signs: red (CZ) vs white w/ red border + blue text (SK).

Temporary square posts in red-white stripes; chevrons white w/ red arrows (rarer red-on-yellow); stripy gas/water poles roadside; hiking markers (colour strip between two white) - most common in CZ+SK

Prefab panel blocks in good condition w/ vibrant colours/patterns (nicer than elsewhere in the ex-East-bloc); diamond-tile roofs (also HU)

Gen3 antenna w/ grey tape on top (also HU/RO/BG); Gen4 red, black or white car (white = CZ, not SK); much grey winter Gen3; rare Gen2 (SK: none)

Slovakia: White Gen4 car, winter Gen3 or Gen2 → Czechia (Slovakia has none of the three).

Hungary: Hungarian (ő ű) → Hungary.

Romania: Romanian ă î ș ț → Romania.

Bulgaria: Cyrillic → Bulgaria.

Black bridge-end signs w/ road number (Gen4)

Czech: Ř Ě Ů (Slovak instead: Ľ Ô Ä Ŕ Ĺ); both use acute vowels (á é í …) - South Slavic doesn't; street = ulice (most Slavic: ulica)

Rolling hills, constant altitude changes, few tall mountains (SK: more mountains AND more true flats); solid outer lines w/o centre line common (also DE)

CZ-vs-SK sign kit: directional signs arrow-shaped w/ filled tip (SK: small white arrows); sign borders separated from the edge (SK: on the edge); highway signs w/ double border; street signs bright red (or blue; SK: white w/ red border + blue text); house numbers blue/red w/ white borders (SK: white w/ red/black border); posts w/ thick black caps (SK: none); ped signs 5 full-size stripes (SK smaller-scale); thin sign font (SK bold); km markers w/ yellow outline, no middle line (SK: middle line, no yellow); railway-cross signs w/o background (SK: white rectangle); bike signs yellow

Suburban houses commonly connected in pairs (rarer in all neighbours)

Road numbers: first digit 1-5 regional (6 scattered; 7/8/9 = Prague northward); 4-digit bike paths increase clockwise from S-Bohemia (A-paths = Prague); area codes = first 1-3 digits (SK numbers start with 0)

Moravia = 95% of Czech wine; N-Bohemia = rolling land + steep solitary hills (sometimes castle-topped)

Architecture regions: timber frames → northern German border; thick dark wooden support poles → far north; dark wooden houses w/ white line stripes → north; Moravian townhouses = long side to the road + barn-sized doors (also NE-Austria); folk baroque (decorated walls) → around České Budějovice; single-pane windows → northwest

Street-sign colours = region: blue → east (Ostrava = only major blue city); white w/ blue text + red border (SK-style) → Slovak border; white w/ red text → east + far south (Brno); white w/ blue text → east + central north; white w/ black text → southeast

City metas: Prague = grey-white marble mosaic pavement (Portugal-like - check city size!); Zlín = functionalist red-brick Baťa cubes; Brno = black+white house-number pairs (district on the black one); Pilsen = two red-white octagonal plates; České Budějovice = red+white underlined plates; Liberec = red numbers w/ dividing line + Roman numeral; Písek = yellow numbers w/ black outline; Šumperk = blue signs, text fills the sign

Polish bilingual street signs → Český Těšín (rarely nearby)